Quarterly Report for Quarter Ending September 30, 2025 (Form 10-Q)

Management's Discussion and Analysis of Financial Condition and Results of Operations

The following discussion and analysis should be read in conjunction with the unaudited financial information and the notes thereto included herein, as well as the "Management's Discussion and Analysis of Financial Condition and Results of Operations" and our audited consolidated financial statements and notes thereto contained in our Annual Report on Form 10-K for the year ended December 31, 2024, as filed on March 31, 2025. This discussion contains forward-looking statements that involve risks and uncertainties. Our actual results and the timing of selected events could differ materially from those anticipated in these forward-looking statements as a result of several factors, including those set forth under the caption "Cautionary Note Regarding Forward-Looking Statements" in this Quarterly Report, as well as under "Part I - Item 1A - Risk Factors" in our Annual Report on Form 10-K for the year ended December 31, 2024, in other subsequent filings with the Securities and Exchange Commission, and elsewhere in this Quarterly Report. These statements, like all statements in this Quarterly Report, speak only as of the date of this Quarterly Report (unless another date is indicated), and the Company undertakes no obligation to update or revise these statements in light of future developments.

Our Management's Discussion and Analysis of Financial Condition and Results of Operations includes the following sections:

Overview

Plus Therapeutics is a U.S. pharmaceutical company developing targeted radiotherapeutics with advanced platform technologies for central nervous system ("CNS") cancers. Our novel radioactive drug formulations and medical device and therapeutic candidates are designed to deliver safe and effective doses of radiation to tumors. To achieve this, we have developed innovative approaches to drug formulation, including encapsulating radionuclides such as rhenium isotopes with nanoliposomes and microspheres. Our formulations are intended to achieve elevated patient-absorbed radiation doses and extend retention times such that the clearance of the isotope occurs after significant and essentially complete radiation decay, which will contribute and provide less normal tissue/organ exposure and improved safety margins.

Traditional approaches to radiation therapy for cancer, such as external beam radiation, have many disadvantages including continuous treatment for four to six weeks (which is onerous for patients), that the radiation damages healthy cells and tissue, and that the amount of radiation delivered is very limited and, therefore, is frequently inadequate to fully destroy the cancer.

Our targeted radiotherapeutic platform and unique investigational drugs have the potential to overcome these disadvantages by directing higher, more powerful radiation doses at the tumor-and only the tumor-potentially in a single treatment. By minimizing radiation exposure to healthy tissues while simultaneously maximizing locoregional delivery and, thereby, efficacy, we hope to reduce the radiation toxicity for patients, improving their quality of life and life expectancy. Our radiotherapeutic platform, combined with advances in surgery, nuclear medicine, interventional radiology, and radiation oncology, affords us the opportunity to target a broad variety of cancer types.

Our lead radiotherapeutic candidate, REYOBIQ (rhenium (186Re) obisbemeda), is designed specifically for CNS cancers including recurrent glioblastoma ("GBM"), leptomeningeal metastases ("LM"), and pediatric brain cancers ("PBC") by direct localized delivery utilizing approved standard-of-care tissue access such as with convection-enhanced delivery ("CED") and intraventricular brain (Ommaya reservoir) catheters. Our acquired radiotherapeutic candidate, Rhenium-188 NanoLiposome Biodegradable Alginate Microsphere ("188RNL-BAM"), is designed to treat many solid organ cancers including primary and secondary liver cancers by intra-arterial injection.

Our cerebrospinal fluid cancer diagnostic portfolio known as the CNSide Platform is currently being utilized in the ReSPECT-LM clinical trial funded by the Cancer Prevention and Research Institute of Texas ("CPRIT"). In connection with our business plan for developing the CNSide Platform, we formed CNSide Diagnostics, LLC ("CNSide Diagnostics"), a wholly owned subsidiary of the Company, and our board of directors appointed a board of managers for CNSide Diagnostics. We are planning for the CNSide Cerebrospinal Fluid Tumor Cell Enumeration test (the "CNSide Test"), which is a laboratory developed test ("LDT"), to be re-introduced to the U.S. market starting in the fourth quarter of 2025. The laboratory for the CNSide Test in Houston, Texas has received a certificate of accreditation from the Centers for Medicare & Medicaid Services (CMS) which deems the lab compliant with Clinical Laboratory Improvement Amendments ("CLIA") regulations. Furthermore, CNSide Diagnostics has signed a national agreement with UnitedHealthcare Insurance Company, effective September 15, 2025, covering over 51 million people throughout the United States, to provide the CNSide Test.

Our headquarters is located in Houston, Texas, in proximity to world-class cancer institutions and researchers.

Pipeline

Our most advanced investigational drug, REYOBIQ, is a patented radiotherapy potentially useful for patients with CNS and other cancers. We announced in March 2025 that the U.S. Food and Drug Administration ("FDA") conditionally accepted the proprietary name REYOBIQ to be used by us for our proprietary rhenium (186Re) obisbemeda. Preclinical study data describing the use of REYOBIQ

for several cancer targets have been published in peer-reviewed journals and reported at a variety of medical society peer-reviewed meetings. Besides GBM, LM and PBC, REYOBIQ has been reported to have potential applications for head and neck cancer, ovarian cancer, breast cancer and peritoneal metastases.

The REYOBIQ technology was part of a licensed radiotherapeutic portfolio that we acquired from NanoTx, Corp. ("NanoTx") on May 7, 2020. The licensed radiotherapeutic has been evaluated in preclinical studies for several cancer targets and we have an active $3.0 million award from U.S. National Institutes of Health/National Cancer Institute which is expected to provide financial support for the continued clinical development of REYOBIQ for recurrent GBM through the completion of a Phase 2 clinical trial, including enrollment of up to 55 patients.

REYOBIQ versus External Beam Radiation Therapy for Recurrent GBM

REYOBIQ is a novel injectable radiotherapy designed to deliver targeted, high dose radiation directly into GBM tumors in a safe, effective, and convenient manner that may ultimately prolong patient survival. REYOBIQ is composed of the radionuclide Rhenium-186 and a nanoliposomal carrier, and is infused in a highly targeted, controlled fashion, directly into the tumor via precision brain mapping and CED catheters. Potential benefits of REYOBIQ compared to standard external beam radiotherapy or external beam radiation therapy ("EBRT") include:

ReSPECT-GBM Trial for Recurrent GBM

GBM affects approximately 15,000 patients annually in the U.S. and is the most common and lethal form of brain cancer. The average life expectancy with GBM is less than 24 months, with a one-year survival rate of 40% and a five-year survival rate of around 5%. There is no clear standard of care for recurrent GBM and the few currently approved treatments provide only marginal survival benefit and are associated with significant side effects, which limit dosing and prolonged use. Approximately 90% of patients experience GBM tumor recurrence at or near the original tumor location, yet there are no FDA-approved treatments in the recurrent or progressive setting that can significantly extend a patient's life. GBM routinely presents with headaches, seizures, vision changes and other significant neurological complications, with a significant compromise in quality of life. Despite the best available medical treatments, the disease remains incurable. Even after efforts to manage the presenting signs and symptoms and completely resect the initial brain tumor, some microscopic disease almost always remains and tumor regrowth occurs within months. Complete surgical removal of GBM is usually not possible and GBM is often resistant or quickly develops resistance to most available current and investigational therapies. Today, the treatment of GBM remains a significant challenge and it has been nearly a decade since the FDA approved a new therapy for this disease, and these more recent approvals have not improved the overall survival ("OS") for GBM patients over past decades, and a significant unmet medical need persists.

While EBRT has been shown to be safe and has temporary efficacy in many malignancies including GBM, typically at absorbed, fractionated radiation dose of ~30 Gray in GBM, this maximum possible administered dose is always limited by toxicity to the normal tissues surrounding the malignancy and because EBRT requires fractionation to manage toxicity and maximum EBRT limits are typically reached before long-term efficacy reached. Because of this limitation, EBRT cannot provide a cure or long-term control of GBM and GBM always recurs within months after EBRT. In contrast, locally delivered and targeted radiopharmaceuticals that precisely deliver radiation in the form of beta particles such as Iodine-131 for thyroid cancer, are known to be safe and effective and minimize exposure to normal cells and tissues especially with optimal administered dose and minimizing exposure to normal tissue. The locally delivered REYOBIQ is designed for and provides patient tolerability and safety. Though no REYOBIQ head-to-head trial with chemo, immune, EBRT or systemic radiopharmaceutical products have been conducted, patient tolerability and safety considerations have been reported as expected.

In September 2020, the FDA granted both orphan drug designation and Fast Track designations to REYOBIQ for the treatment of patients with GBM.

REYOBIQ is under clinical investigation in a Phase 1/2 multicenter, sequential cohort, open-label, volume and dose escalation study ("ReSPECT-GBM") of the safety, tolerability, and distribution of REYOBIQ given by CED catheters to patients with recurrent or progressive malignant glioma after standard surgical, radiation, and/or chemotherapy treatment. The trial is funded through Phase 2 in large part by a National Institute of Health/National Cancer Institute grant.

We completed Phase 1 of our ReSPECT-GBM Trial and are targeting full enrollment into Phase 2 by the end of 2026.

ReSPECT-LM Clinical Trials for LM

LM is a rare complication of cancer in which the disease spreads to the membranes (meninges) surrounding the brain and spinal cord. The incidence of LM is growing and occurs in approximately 5%, or more, of people with late-stage cancer, or 110,000 people in the U.S. each year. It is highly lethal with an average one-year survival of just 7%. All solid cancers, particularly breast, lung, GI, and melanoma, have the potential to spread to the leptomeninges.

The ReSPECT-LM Phase 1 clinical trial (ClinicalTrials.gov NCT05034497) was preceded with preclinical studies in which tolerance to doses of REYOBIQ as high as 1,075 Gy were shown in animal models with LM without significant observed toxicity. Furthermore, treatment led to a marked reduction in tumor burden in both C6 and MDA-231 LM models.

Upon receiving acceptance of our Investigational New Drug application and Fast Track designation by the FDA for REYOBIQ for the treatment of LM in November 2021, we initiated the trial and began screening patients for the ReSPECT-LM Phase 1 clinical trial in the fourth quarter of 2021.

ReSPECT-LM is a multi-center, sequential cohort, open-label, dose escalation study evaluating the safety, tolerability, and efficacy of a single-dose application of REYOBIQ administered through intrathecal infusion to the ventricle of patients with LM after standard surgical, radiation, and/or chemotherapy treatment. The primary endpoint of the study is the incidence and severity of adverse events and dose limiting toxicities, together with determining the maximum tolerated and recommended Phase 2 dose. Full enrollment in the Phase 1 trial was achieved at the end of 2024, and we announced the trial completion on February 26, 2025. Trial closeout procedures are now taking place including final data review and monitoring, and a clinical study report and manuscript will be prepared.

On September 19, 2022, we entered into a Cancer Research Grant Contract (the "CPRIT Contract"), effective as of August 31, 2022, with CPRIT, pursuant to which CPRIT provides us a grant of up to $17.6 million (the "CPRIT Grant") over a three-year period to fund the continued development of REYOBIQ for the treatment of patients with LM through Phase 2 of the ReSPECT-LM clinical trial. The CPRIT Grant is subject to customary CPRIT funding conditions, including, but not limited to, a matching fund requirement (one dollar from us for every two dollars awarded by CPRIT), revenue sharing obligations upon commercialization of REYOBIQ based on specific dollar thresholds until CPRIT receives the aggregate amount of 400% of the proceeds awarded under the CPRIT Grant, and certain reporting requirements. As of September 30, 2025, we had received approximately $14.3 million in milestone payments under the CPRIT Contract.

Interim results show that a single treatment with REYOBIQ resulted in a consistent decreased cerebrospinal fluid ("CSF") tumor cell count/ml and is tolerated by all LM patients. REYOBIQ is an outpatient administration and treatment and is easily and safely administered through a standard intraventricular catheter (Ommaya Reservoir), distributed promptly throughout the CSF, and with durable retention in the leptomeninges at least through day seven. All patients have shown well tolerated prompt and durable REYOBIQ distribution throughout the subarachnoid space.

Our ReSPECT LM Multi-dose Phase 1/2 Study is currently enrolling patients.

ReSPECT-PBC Clinical Trial for Pediatric Brain Cancer

The average annual age adjusted mortality rate for children aged 0-14 for malignant brain (and other CNS) tumors is 0.71/100,000, making it the most common cause of death and cancer death in this age group. The 2021 World Health Organization Classification of CNS Tumors classifies gliomas, glioneuronal tumors, and neuronal tumors into six different families: (1) adult-type diffuse gliomas; (2) pediatric-type diffuse low-grade gliomas; (3) pediatric-type diffuse high-grade gliomas ("HGG"); (4) circumscribed astrocytic gliomas; (5) glioneuronal and neuronal tumors; and (6) ependymomas.

In August 2021, we announced plans for treating pediatric brain cancer at the 2021 American Association of Neurological Surgeons Annual Scientific Meeting. In July 2021, we reported that we received FDA feedback pertaining to a pre-Investigational New Drug Application ("IND") meeting briefing package in which the FDA stated that we are not required to perform any additional preclinical or toxicology studies.

Pediatric high-grade gliomas can be found almost anywhere within the CNS; however, they are most commonly found within the supratentorium. The highest incidence of supratentorial, high-grade gliomas in pediatrics appears to occur in children aged 15 to 19 years, with a median age of approximately nine years. Overall, pediatric high-grade glioma confers a three-year progression free survival ("PFS") of 11 ± 3% and three-year OS of 22 ±5%. One-year PFS is as low as 40% in recent trials. Ependymomas are slow-growing central nervous system tumors that involve the ventricular system. Diagnosis is based on MRI and biopsy and survival rate depends on tumor grade and how much of the tumor can be removed. Grade II pathology was associated with significantly improved OS compared to Grade III (anaplastic) pathology (five-year OS = 71 ± 5% vs. 57 ± 10%; p = 0.026). Gross total resection compared to subtotal resection was associated with significantly improved OS (five-year OS = 75 ± 5% vs. 54 ± 8%; p = 0.002).

Overall, pediatric HGG and ependymoma are extremely difficult-to-treat pediatric brain tumors, frequently aggressive, and in recurrent settings, carry an extremely poor prognosis.

Effective September 1, 2024, we entered into an agreement with the Department of Defense office of the Congressionally Directed Medical Research Programs to receive a $3.0 million fund for research and development purposes ("DoD Award") over a three-year

period. The DoD Award will be used to support the planned expansion of our clinical trial for pediatric brain cancer. We anticipate beginning enrollment for our Phase 1 ReSPECT-PBC clinical trial in 2025.

On June 25, 2025, we announced that the FDA cleared its Investigational New Drug ("IND") application (No. 168178) for REYOBIQ for the treatment of pediatric patients with supratentorial recurrent, refractory, or progressive high-grade glioma ("HGG") and ependymoma. The Phase 1/2a trial is a two-part, single-arm, prospective study aimed at determining the maximum tolerated dose ("MTD"), safety, and tolerability of REYOBIQ in pediatric patients aged 6 to 21 years (with consideration for patients up to 25 years on a case-by-case basis).

Key elements of the trial design include:

Rhenium-188 NanoLiposome Biodegradable Alginate Microsphere Technology

In January 2022, we announced that we licensed Biodegradable Alginate Microsphere ("BAM") patents and technology from The University of Texas Health Science Center at San Antonio ("UTHSCSA") to expand our tumor targeting capabilities and precision radiotherapeutics pipeline. We intend to combine our Rhenium NanoLiposome technology with the BAM technology to create a novel radioembolization technology. Initially, we intend to utilize the Rhenium-188 isotope, 188RNL-BAM for the intra-arterial embolization and local delivery of a high dose of targeted radiation for a variety of solid organ cancers such as hepatocellular cancer, hepatic metastases, pancreatic cancer and many others.

Preclinical data from an ex vivo embolization experiment in which Technetium99m-BAM was intra-arterially delivered to a bovine kidney perfusion model was presented at the Society of Interventional Radiology Annual Scientific Meeting. The study concluded that the technology required for radiolabeling BAM could successfully deliver, embolize and retain radiation in the target organ. 188RNL-BAM is a preclinical investigational device we intend to further develop and move into clinical trials. Specifically, in 2022 we transferred the 188RNL-BAM technology from UTHSCSA, and began planning to develop the product and complete early preclinical studies to support a future FDA IND submission. Our intended initial clinical target is liver cancer which is the sixth most common and third deadliest cancer worldwide. It is a rare disease with increasing U.S. annual incidence (42,000) and deaths (30,000).

The FDA has informed us that 188RNL-BAM will be regulated as a medical device under the FDCA.

The CNSide FORESEE Trial

The CNSide Platform consists of four LDTs used for treatment selection and treatment monitoring of patients with LM. The CNSide Platform facilitates tumor cell detection/enumeration and biomarker identification using cellular assays (immunocytochemistry (ICC) and fluorescence in situ hybridization (FISH)) and molecular assays (next-generation sequencing (NGS)). The CNSide Test is currently being used in the ReSPECT-LM trial as an exploratory endpoint.

Since acquiring the CNSide Platform in 2024, we have established infrastructure to support a scalable and centralized testing laboratory in Houston, TX that will service the U.S. market. We have been executing on our commercial market access strategy, which includes prioritized state licensure, proprietary reimbursement codes, commercial and government payor coverage, and value-based pricing to optimize revenue. We anticipate introducing the CNSide Platform first in Texas in the second half of 2025, followed rapidly by expansion into additional states in 2026. In parallel, additional expanded CNS testing capabilities are also expected to roll out over the next year.

When the CNSide CSF Assay Platform was previously commercially available, market acceptance and adoption were widespread, with several national and regional commercial payor agreements in place and the test in regular use at major cancer centers across the U.S. We are now in contact with the legacy payors and healthcare providers in anticipation of the planned 2025 launch, and later this year will be expanding those contacts to support a 50-state strategy. Finally, we have hired experienced leadership with expertise in the development and commercialization of clinical diagnostic technologies on a large scale.

Recent Developments

Recent Financings

Refer to the "Liquidity and Capital Resources" section below for information on our recent financings.

Financing Related Transactions

As of September 30, 2025, we recorded a $6.4 million liability in accounts payable and accrued expenses due to the March 2025 Private Placement Purchasers. Such liability declined by $1.3 million from September 30, 2025 to October 27, 2025 due to 1) a $0.9 million reduction as a result of the reselling of securities acquired in the March 2025 Private Placement by certain March 2025 Private Placement Purchasers, which was recorded as a reduction of liability that would have been settled in cash, with a corresponding increase to

stockholders' equity, and 2) a payment of $0.4 million to the March 2025 Private Placement Purchasers subsequent to September 30, 2025, with 0.6 million shares of the Company's common stock returned and cancelled under the terms of the Letter Agreement.

On October 28, 2025, we entered into an amendment to the Letter Agreement and the Support Letters with certain March 2025 Private Placement Purchasers (the "Amendment Agreement"), pursuant to which (a) the Support Letters were terminated other than with respect to the participation rights granted therein, and (b) the repayment mechanism under the Letter Agreement was modified. As modified, we are no longer required to use 90% of the proceeds from any subsequent financing to repay the March 2025 Private Placement Purchasers. Instead, we are only required to retain sufficient funds in an interest bearing account to cover such repayment obligations and make such repayments upon request by any March 2025 Private Placement Purchaser who executed the Amendment Agreement until each such purchaser has received cash either from us or from reselling securities acquired in the March 2025 Private Placement in an amount equal to 115% of the purchase price such purchaser paid in the March 2025 Private Placement. If such requests are made, the requesting purchaser must return shares acquired in the March 2025 Private Placement at a value of $0.66 per share.

In addition, we issued approximately 3.3 million shares on the Lincoln Park Purchase Credit Agreement, raising an additional $1.9 million of capital through October 29, 2025.

Houston Lease

On October 16, 2025, we entered into a lease (the "Houston Lease") with LG 1 Property Owner LP, pursuant to which we agreed to lease approximately 11,370 rentable square feet of space located at 6420 Levit Green Boulevard, Houston, Texas 77021. The Houston Lease is expected to commence on or about November 1, 2026. The Houston Lease provides for a monthly base rent of $58,745, which increases annually by approximately 3%, plus our share of the building's direct expenses. The Houston Lease has an initial term of 120 calendar months.

Results of Operations

Grant Revenue

We recognized $1.4 million and $3.8 million, and $1.5 million and $4.4 million of grant revenue during the three and nine months ended September 30, 2025 and 2024, respectively, which represents CPRIT's share of the costs incurred for our rhenium (186Re) obisbemeda development for the treatment of patients with LM.

Research and development expenses

Research and development expenses include costs associated with the design, development, testing, and enhancement of our product candidates, payment of regulatory fees, laboratory supplies, preclinical studies, and clinical studies.

The following table summarizes the components of our research and development expenses for the three and nine months ended September 30, 2025 and 2024 (in thousands):

Research and development expenses decreased by approximately $0.4 million during the three months ended September 30, 2025 as compared to the same period in 2024. The decrease was due primarily to a decrease of $0.4 million in development expenses, a decrease of $0.4 million in compensation expense, a decrease of $0.4 million in professional research and development services, and a decrease of $0.1 million in depreciation expense. These decreases were partially offset by an increase of $0.5 million in licensing expenses and an increase of $0.4 million in diagnostics.

Research and development expenses decreased by approximately $3.0 million during the nine months ended September 30, 2025 as compared to the same period in 2024. The decrease was due primarily to a decrease of $1.3 million in clinical expenses, a decrease of $1.1 million in compensation expense, a decrease of $0.7 million in professional services, a decrease of $0.3 million in development expenses, a decrease of $0.2 million in depreciation expense and a decrease of $0.1 million in travel costs. These decreases were partially offset by an increase of $0.4 million in diagnostics, and $0.3 million in licensing expenses.

We expect aggregate research and development expenses to increase during the remainder of 2025 as compared to the corresponding comparable period in 2024 as we commence the ReSPECT-LM dose optimization trial for REYOBIQ and prepare for the launch of the CNSide Test.

General and administrative expenses

General and administrative expenses include costs for administrative personnel, legal and other professional expenses, and general corporate expenses. The following table summarizes the general and administrative expenses for the three and nine months ended September 30, 2025 and 2024 (in thousands):

General and administrative expenses increased by $1.0 million during the three months ended September 30, 2025, as compared to the same period in 2024, primarily due to an increase of $0.6 million in compensation expense, an increase of $0.3 million in legal and professional fees, and an increase of $0.1 million in accounting expenses.

General and administrative expenses increased $1.2 million during the nine months ended September 30, 2025, as compared to the same period in 2024, primarily due to an increase of $1.3 million in compensation expense, partially offset by a decrease of $0.1 million in legal and professional services.

We expect general and administrative expenditures to increase during the remainder of 2025 as compared to the corresponding comparable period in 2024 as we work towards the commercial launch of the CNSide Test, which will require an increase in administrative and sales headcount.

Stock-based compensation expense

Stock-based compensation expense includes charges related to equity awards issued to employees, directors and non-employees. We measure stock-based compensation expense based on the grant-date fair value of any awards granted to our employees. Such expense is recognized over the requisite service period.

The following table summarizes the components of our stock-based compensation expenses for the three and nine months ended September 30, 2025 and 2024 (in thousands):

Our stock-based compensation expense is impacted by grants of equity awards, the vesting schedule of such grants, as well as the grant date fair value of equity awards. Stock-based compensation expense increased during the three and nine months ended September 30, 2025 as compared to the same periods in 2024 primarily due to an increase in the number of awards granted, which was partially offset by a decrease in the grant date fair value of equity awards granted.

Financing items

The following table summarizes non-operating income and expenses for the three and nine months ended September 30, 2025 and 2024 (in thousands):

Interest income decreased for the three and nine months ended September 30, 2025 compared with the same period in 2024 primarily due to reduced accreted income on our available-for-sale securities in 2024 and a lower interest rate environment in 2025.

The decrease in interest expense for the three months ended September 30, 2025 as compared to the same period in 2024 was due to the January 2025 payoff of the Pershing Credit Facility. The increase in interest expense for the nine months ended September 30, 2025 as compared to the same period in 2024 was due to interest expense incurred in connection with the Funding Notes and Exchange Notes issued in February 2025, partially offset by the January 2025 payoff of the Pershing Credit Facility.

The decrease in financing expenses for the nine months ended September 30, 2025 as compared to the same period in 2024 was primarily due to the March 2025 PIPE and May 2024 PIPE transactions.

The change in the fair value of the derivative instruments for the three months ended September 30, 2025 as compared to the same period in 2024 was due to the March 2025 Private Placement and May 2024 Private Placement and accompanying warrants issued in both financings. The change in the fair value of the derivative instruments for the nine months ended September 30, 2025 as compared

to the same period in 2024 was primarily due to the March 2025 Private Placement (specifically the liability classified March 2025 Series B Warrants, which were remeasured immediately prior to exercise, before being reclassified as equity), offset by the May 2024 Private Placement (specifically the May 2024 Series A Warrants and May 2024 Series B Warrants, which were initially classified as liabilities before being reclassified as equity).

The decrease in warrant issuance costs for the three months ended September 30, 2025 as compared to the same period in 2024, was due to warrant issuance costs related to the May 2024 Private Placement. The increase in the warrant issuance costs for the nine months ended September 30, 2025 as compared to the same period in 2024 was due to the warrant issuance costs from the March 2025 Private Placement and May 2024 Private Placement.

Liquidity and Capital Resources

Short-term and long-term liquidity

The following is a summary of our key liquidity measures at September 30, 2025 and December 31, 2024 (in thousands):

We incurred net losses of $16.7 million for the nine months ended September 30, 2025. We have an accumulated deficit of $510.2 million as of September 30, 2025. Additionally, we used net cash of $14.5 million to fund our operating activities for the nine months ended September 30, 2025. These factors raise substantial doubt about our ability to continue as a going concern.

To date, our operating losses have been funded primarily from outside sources of invested capital, from issuance of our common and preferred equity, proceeds from our now-repaid in full term loan with Oxford Finance, LLC ("Oxford"), our line of credit facility with Pershing LLC and grant funding. We have had, and will continue to have, an ongoing need to raise additional cash from outside sources to fund our future clinical development programs and other operations, and commercialize the CNSide Test. There can be no assurance that we will be able to continue to raise additional capital in the future. Our inability to raise additional cash would have a material and adverse impact on our operations and ability to satisfy our obligations.

February 2025 SPEA

On February 13, 2025 (the "February 2025 SPEA Closing Date"), we entered into a securities purchase and exchange agreement (the "February 2025 SPEA") with certain existing accredited investors. Pursuant to the February 2025 SPEA, on the February 2025 SPEA Closing Date we issued secured convertible promissory notes (the "Funding Notes") in the aggregate principal amount of $3.3 million together with common stock purchase warrants (the "February 2025 Warrants") to purchase 3,002,009 shares of our common stock at an exercise price of $1.12 per share. The aggregate purchase price for the Funding Note and February 2025 Warrants was approximately $3.7 million and included payment of $0.125 per February 2025 Warrant in accordance with the listing rules of Nasdaq.

Exchange Notes

The May 2024 Purchase Agreement (as described below) included certain limitations and restrictions on our ability to issue securities and provided the May 2024 Private Placement Purchasers other than our directors and executive officers (the "Outside Investors") participation rights in future equity and equity-linked offerings of securities, subject to certain limited exceptions (the "Financing Restrictions"). On the February 2025 SPEA Closing Date, pursuant to the February 2025 SPEA, we issued to the Outside Investors secured convertible promissory notes in the aggregate amount of $3.2 million (the "Exchange Notes") in exchange for cancellation of the 3,543,247 May 2024 Series A Warrants held by them, and the Outside Investors entered into a second amendment to the May 2024 Purchase Agreement to eliminate the Financing Restrictions.

As described below, we repurchased the Funding Notes and issued common stock and warrants for cancellation of the Exchange Notes in connection with the March 2025 Private Placement.

March 2025 Private Placement

On March 4, 2025, we entered into a securities purchase agreement (the "March 2025 Purchase Agreement") with accredited investors, including certain of our existing stockholders, identified on the signature page thereto (collectively, the "March 2025 Private Placement Purchasers") for a private placement of securities (the "March 2025 Private Placement") for gross proceeds of approximately $15.0 million. Pursuant to the March 2025 Purchase Agreement, we issued an aggregate of 4,069,738 shares (the "March 2025 Private Placement Shares") of our common stock and 23,972,400 Pre-Funded Warrants, with each March 2025 Private Placement Share or Pre-Funded Warrant accompanied by (i) a Series A common warrant (the "March 2025 Series A Warrants") to purchase one share of common stock and (ii) one Series B common warrant (the "March 2025 Series B Warrants") to purchase one share of common stock.

The combined purchase price of $0.66 for each March 2025 Private Placement Share or $0.659 for each Pre-Funded Warrant in the March 2025 Private Placement, together with one accompanying March 2025 Series A Warrant and one accompanying March 2025 Series B Warrant, represented the applicable "Minimum Price" in accordance with Listing Rule 5635(d) of Nasdaq.

The initial exercise price of each March 2025 Series A Warrant is $1.32 per share of common stock. The March 2025 Series A Warrants are exercisable only following stockholder approval and expire five (5) years thereafter. The March 2025 Series A Warrants are subject to certain price reset, share combination event and anti-dilution provisions which, if triggered, provide that the number of shares issuable upon exercise of the March 2025 Series A Warrants will downward adjust, subject to the Floor Price, and the number of shares issuable upon exercise therefor will increase such that the aggregate exercise price remains unchanged.

The initial exercise price of each March 2025 Series B Warrant is $1.98 per share of common stock. The March 2025 Series B Warrants are exercisable only following stockholder approval and expire two and one-half (2.5) years thereafter. The March 2025 Series B Warrants are subject to certain price reset and share combination event provisions which, if triggered, provide that the number of shares issuable upon exercise of the March 2025 Series B Warrants will downward adjust, subject to the Floor Price, and the number of shares issuable upon exercise therefor will increase such that the aggregate exercise price remains unchanged. In addition, the March 2025 Series B Warrant alternative cashless exercise provision provides that the March 2025 Series B Warrant can be exercised without further payment to us and for three times the number of shares of common stock then subject to the March 2025 Series B Warrant.

Of the securities issued in the March 2025 Private Placement, 3,077,270 shares of Common Stock, 19,650,000 shares of March 2025 Pre-Funded Warrants in lieu thereof, and the accompanying 22,727,270 March 2025 Series A Warrants and 22,727,270 March 2025 Series B Warrants, were issued in consideration of new capital subscriptions, and 992,468 shares of Common Stock, 4,322,400 March 2025 Pre-Funded Warrants in lieu thereof, and the accompanying 5,314,870 March 2025 Series A Warrants and 5,314,870 March 2025 Series B Warrants, were issued in exchange for the cancelation of the Exchange Notes.

The March 2025 Private Placement closed on March 7, 2025. The aggregate gross proceeds at the closing were approximately $15.0 million, before deducting $1.4 million of expenses payable by us.

On May 2, 2025, our stockholders approved, among other things, the March 2025 Series A Warrants and March 2025 Series B Warrants and an amendment of our Certificate of Incorporation, as amended, to increase the authorized share capital to an amount sufficient to cover the shares of common stock issuable upon the exercise of the March 2025 Series A Warrants and March 2025 Series B Warrants. As part of the March 2025 Series A Warrants and March 2025 Series B Warrants agreement, the exercise price of the March 2025 Series A Warrants and March 2023 Series B Warrants were reset on May 19, 2025 to $0.4373 per share. Prior to modification of the March 2025 Series B Warrants as part of the Letter Agreement (as further described below), certain March 2025 Series B Warrants were cashless exercised for the issuance of 21,482,492 shares of common stock. The liability classified March 2025 Series B Warrants were remeasured immediately prior to exercise, which resulted in a $3.8 million gain on the change in fair value for the nine months ended September 30, 2025, and a $0.8 million credit to additional paid-in-capital.

Letter Agreement

On June 17, 2025, the Company and the Purchasers entered into a letter agreement (the "Letter Agreement") with each of the Purchasers in an effort to, among other items, minimize the dilutive impact of the March 2025 Private Placement. The Letter Agreement extinguished the March 2025 Series A Warrants, modified the March 2025 Series B Warrants, and provided for the return of Private Placement Shares and Pre-Funded Warrants, as further discussed in the following paragraphs.

As part of the Letter Agreement, all March 2025 Series A Warrants were cancelled, which resulted in a $2.7 million gain on change in fair value recorded as capital contribution to additional paid-in capital, as the extinguishment was deemed equivalent to a capital contribution by existing shareholders of the Company.

As part of the same transaction, the March 2025 Series B Warrants were amended ("Amended March 2025 Series B Warrants"), to (a) reduce the overall number of March 2025 Series B Warrant Shares issuable upon exercise of the Series B Warrants to an aggregate of up to 35,536,380 Series B Warrant Shares, (b) reduce the alternative cashless exercise ratio in such March 2025 Series B Warrants from 3:1 to 1:1, and (c) remove provisions contained in the March 2025 Series B Warrants that would otherwise reduce the Company's stockholders' equity. As a result of the Letter Agreement, the Amended March 2025 Series B Warrants no longer fail the indexation guidance under ASC 815, Derivatives and Hedging, and the fair value of the warrant liability, in the amount of $11.0 million was reclassified to equity. Immediately prior to reclassification, the March 2025 Series B Warrant liability was remeasured, and $4.5 million was recorded as a capital contribution to additional paid-in capital, as the modification of the March 2025 Series B Warrants was deemed equivalent to a capital contribution by existing shareholders of the Company. After the June 17, 2025 modification, 34,794,54 Amended March 2025 Series B Warrants were cashless exercised.

Lastly, in conjunction with the Letter Agreement, each of the March 2025 Private Placement Purchasers agreed to return an aggregate of 12,241,986 Private Placement Shares and Pre-Funded Warrants issuable for an aggregate of 10,633,650 Pre-Funded Warrant Shares, held by them as of the date of the Letter Agreement, upon request of the Company (the "Letter Agreement Repurchase Option"), which were issued pursuant to the March 2025 Private Placement Purchase Agreement for a value of $0.66 per Private Placement Share and $0.659 per Pre-Funded Warrant. In exchange therefor, the Company agreed to repay the March 2025 Private Placement Purchasers holding such securities 115% of such value, using 90% of the proceeds from any capital raised by the Company subsequent to July 1, 2025. The Company and each of the March 2025 Private Placement Purchasers also agreed to waive any restrictions on subsequent equity sales and variable rate transactions contained in March 2025 Private Placement Purchase Agreement to allow for such repayment.

During the three and nine months ended September 30, 2025, we paid the March 2025 Private Placement Purchasers $2.3 million and 3,472,740 shares were returned and cancelled under the terms of the Letter Agreement.

Support Letters

On July 11, 2025, we and certain March 2025 Private Placement Purchasers party to the Letter Agreement entered into that certain letter of support (the "Support Letters") to modify certain portions of the Letter Agreement as between us and each of such March 2025 Private Placement Purchasers. In the event that we reasonably believe that, within the 30 days (the "Modification Period") prior to the end of any fiscal quarter, we will have stockholders' equity in an amount below $3.0 million as of the end of such fiscal quarter (the "Potential Equity Deficiency"), the Subsequent Financing Percentage (as defined in the Letter Agreement) shall be modified from 90% to 50% for any Subsequent Financing (as defined in the Letter Agreement) that occurs during the Modification Period pursuant to the Lincoln Park Purchase Agreement. Upon the end of the Modification Period, the Subsequent Financing Percentage shall be reverted to 90%, and such percentage shall apply to all Subsequent Financings, including all Subsequent Financings pursuant to the Lincoln Park Purchase Agreement. In the event we desire to trigger the modification of the Subsequent Financing Percentage, we agree to supply the purchaser who executed a Support Letter with a pro forma balance sheet to evidence its reasonable belief of the Potential Equity Deficiency approximately 30 days prior to each end of fiscal quarter once the books for prior months are closed. In accordance with the Support Letters, we made a cash payment of $0.5 million to each purchaser for a total cash payment of $2.3 million, which was recorded as a reduction to additional paid-in capital in the condensed consolidated balance sheet as of September 30, 2025. Such payment counted as cash received by the purchaser towards its Maximum Amount. Each Support Letter also grants the purchaser party to the letter a participation right in certain future financings of ours for a period of 12 months.

First Amendment to the February 2025 SPEA

In connection with the March 2025 Purchase Agreement, we entered into that certain First Amendment to the February 2025 SPEA (the "First Amendment"). The February 2025 SPEA included certain limitations and restrictions on our ability to issue securities and provided the investors participation rights in future equity and equity-linked offerings of securities, subject to certain limited exceptions (the "New Financing Restrictions"). Pursuant to the First Amendment, subject to consummation of the March 2025 Private Placement, we agreed to repurchase from the Investors $3.4 million in principal amount of the Funding Notes and accrued interest, along with the February 2025 Warrants issued pursuant to the February 2025 SPEA for an aggregate purchase price of $4.2 million. In exchange for the repurchase by us of the Funding Notes and February 2025 SPEA Warrants, the February 2025 Purchasers agreed to consent to the March 2025 Private Placement and eliminate the New Financing Restrictions.

May 2024 Private Placement

In May 2024, we entered into a securities purchase agreement (the "May 2024 Purchase Agreement"), which was subsequently amended, with certain investors, including certain of the our directors and executive officers (the "May 2024 Private Placement Purchasers"), whereby we issued and sold in a private placement (the "May 2024 Private Placement"): (i) 3,591,532 shares of common stock or, at the election of each investor, Pre-Funded warrants ("May 2024 Pre-Funded Warrants") to purchase shares of common stock exercisable immediately at an exercise price of $0.001 per share. Each share or May 2024 Pre-Funded Warrant was accompanied by (i) a Series A common warrant ("May 2024 Series A Warrants") to purchase one share of common stock, for an aggregate of 3,591,532 Series A Warrants, and (ii) one Series B common warrant ("May 2024 Series B Warrants") to purchase one share of common stock, for an aggregate of 3,591,532 May 2024 Series B Warrants. At the closing of the May 2024 Private Placement, we received net proceeds of approximately $7.3 million.

Lincoln Park Purchase Agreement

On June 17, 2025, we entered into a purchase agreement (the "Lincoln Park Purchase Agreement") and a registration rights agreement pursuant to which Lincoln Park Capital Fund ("Lincoln Park") committed to purchase up to $50.0 million of shares of our common stock. Under the terms and subject to the conditions of the Lincoln Park Purchase Agreement, we have the right, but not the obligation, to sell to Lincoln Park, and Lincoln Park is obligated to purchase up to $50.0 million of shares of our common stock. Sales of common stock by us are subject to certain limitations, and can occur from time to time, at our sole discretion, over the 36-month period commencing on June 23, 2025, subject to the satisfaction of certain conditions. Actual sales of shares of common stock to Lincoln Park under the Lincoln Park Purchase Agreement depend on a variety of factors to be determined by us from time to time, including, among others, market conditions, the trading price of the common stock and our determinations as to the appropriate sources of funding for the Company and its operations. As consideration for Lincoln Park's irrevocable commitment to purchase shares of our common stock upon the terms of and subject to satisfaction of the conditions set forth in the Lincoln Park Purchase Agreement,

On June 23, 2025, a registration statement (the "Initial Registration Statement") was declared effective covering the resale of up to 17,000,000 shares of our common stock. On August 14, 2025, a registration statement (the "Second Registration Statement") was declared effective covering the resale of up to 33,000,000 shares of our common stock.

In accordance with the Lincoln Park Purchase Agreement, we were required to pay Lincoln Park an initial commitment fee of $0.5 million, which was paid through the issuance of 1,612,903 shares of common stock on August 14, 2025. The initial commitment fee was recorded as a reduction to additional paid-in capital in the condensed consolidated balance sheet as of September 30, 2025. An additional commitment fee of $0.5 million will be paid in cash or shares of common stock, or a combination of cash and shares of common stock, if and when we sell over $25.0 million of our common stock under the Lincoln Park Purchase Agreement.

As of the nine months ended September 30, 2025, we issued 44,575,496 shares under the Lincoln Park Purchase Agreement for gross proceeds of approximately $19.6 million. The Company incurred approximately $50,000 for legal fees in connection with the Lincoln Park Purchase Agreement.

Subsequent to September 30, 2025, we issued 3.3 million shares under the Lincoln Park Purchase Agreement, raising an additional $1.9 million of capital through October 29, 2025.

CPRIT Grant

On September 19, 2022, we entered into the CPRIT Contract, pursuant to which CPRIT will provide us with the CPRIT Grant of $17.6 million subject to the terms of the CPRIT Contract, to fund approximately two-thirds of the continued development of REYOBIQ for the treatment of patients with LM. We recognized $3.8 million, $5.8 million, $4.9 million and $0.2 million of grant revenue during the nine months ended September 30, 2025, years ended December 31, 2024, 2023 and 2022, respectively, all of which has been received. The amounts recognized represents CPRIT's share of the costs incurred for our REYOBIQ development for the treatment of patients with LM. As of September 30, 2025, we had $1.1 million of deferred grant liability related to the CPRIT Grant.

Nasdaq Listing Compliance

On March 8, 2024, we received notice from the Listing Qualifications staff of Nasdaq (the "Staff"), notifying us that we no longer complied with the requirement under Nasdaq Listing Rule 5550(b)(1) to maintain a minimum of $2.5 million in stockholders' equity (the "Minimum Stockholders' Equity Requirement") for continued listing on The Nasdaq Capital Market or the alternative requirements of having a market value of listed securities of $35 million or net income from continuing operations of $500,000 in the most recently completed fiscal year or two of the last three most recently completed fiscal years.

On September 5, 2024, Nasdaq notified us that we had not regained compliance with Nasdaq Listing Rule 5550(b)(1). We requested a hearing before the Nasdaq hearing panel and on October 30, 2024, we received a decision from the panel, notifying us that we had until March 4, 2025 to demonstrate compliance with the Minimum Stockholders' Equity Requirement.

On March 7, 2025, we received notification from Nasdaq that it had regained compliance with the Minimum Stockholders' Equity Requirement due to the March 2025 Private Placement.

Pursuant to Nasdaq Listing Rule 5815(d)(4)(B), we will be subject to a Mandatory Panel Monitor until March 7, 2026. If the Staff finds us again out of compliance with the Minimum Stockholders' Equity Requirement before that date, we would not be permitted to provide the Staff with a plan of compliance with respect to that deficiency and the Staff would not be permitted to grant additional time for us to regain compliance with respect to that deficiency, nor would we be afforded an applicable cure or compliance period. Instead, the Staff would issue a "Delist Determination Letter" and we would have an opportunity to request a hearing before the panel regarding our continued listing.

Furthermore, on May 16, 2025, we received notice from Nasdaq that, because the closing bid price for our common stock has fallen below $1.00 per share for 30 consecutive business days, we no longer comply with the minimum bid price requirement pursuant to Nasdaq Listing Rule 5550(a)(2) (the "Minimum Bid Requirement").

Nasdaq's Minimum Bid Requirement notice has no immediate effect on the listing or trading of our common stock. Pursuant to Nasdaq Listing Rule 5810(c)(3)(A), we are provided an initial compliance period of 180 calendar days, or until November 12, 2025, to regain compliance with the Minimum Bid Requirement. To regain compliance, the closing bid price of our common stock must meet or exceed $1.00 per share for a minimum of 10 consecutive business days prior to November 12, 2025.

If we do not achieve compliance with the Minimum Bid Requirement by November 12, 2025, we may be eligible for an additional 180 calendar days to regain compliance. To qualify, we would be required to meet the continued listing requirement for market value of publicly held shares and all other Nasdaq initial listing standards, with the exception of the Minimum Bid Requirement, and provide written notice of its intention to cure the minimum bid price deficiency during the second compliance period by effecting a reverse stock split if necessary. If the Staff determines that we will not be able to cure the deficiency, or if we are otherwise not eligible for such additional compliance period, Nasdaq will provide notice that our common stock will be subject to delisting. In the event we receive notice that its common stock is being delisted, Nasdaq rules permit us to appeal any delisting determination by the Staff.

We intend to monitor the closing bid price of our common stock and may, if appropriate, consider implementing available options to regain compliance with the Minimum Bid Requirement.

On May 2, 2025, our stockholders granted discretionary authority to our board of directors to (i) amend our Certificate of Incorporation to combine outstanding shares of our common stock into a lesser number of outstanding shares, or a "reverse stock split," at a specific ratio within a range of one-for twenty five (1-for-25) to a maximum of one-for-two hundred fifty (1-for-250), with the exact ratio to be determined by the board of directors in its sole discretion; and (ii) effect the reverse stock split, if at all, within twelve (12) months of the date the proposal is approved by stockholders.

In addition, on August 7, 2025, the stockholders granted discretionary authority to the Company's board of directors to (i) amend the Company's Certificate of Incorporation to combine outstanding shares of the Company's common stock into a lesser number of outstanding shares, or a "reverse stock split," at a specific ratio within a range of one-for two (1-for-2) to a maximum of one-for-two

hundred fifty (1-for-250), with the exact ratio to be determined by the board of directors in its sole discretion; and (ii) effect the reverse stock split, if at all, within twelve (12) months of the date the proposal is approved by stockholders.

On June 3, 2025, the Staff notified the Company that it was not in compliance with the Minimum Stockholders' Equity Requirement (the "June 3 Letter"). The Company reported stockholders' equity (deficit) of ($23,641,000) in its Quarterly Report on Form 10-Q for the period ended March 31, 2025, and, as a result, did not satisfy the Minimum Stockholders' Equity Requirement pursuant to Listing Rule 5550(b)(1). As a result, the Staff determined to delist the Company's securities from Nasdaq, unless the Company timely requests an appeal of the Staff's determination to a Hearings Panel (the "Panel"), pursuant to the procedures set forth in the Nasdaq Listing Rule 5800 Series. The Company timely requested a hearing, which hearing took place as scheduled on July 15, 2025.

On July 22, 2025, the Panel issued a decision (the "July 2025 Decision") granting the Company's request for continued listing on Nasdaq, subject to the Company demonstrating compliance with (1) the Minimum Stockholders' Equity Requirement pursuant to Listing Rule 5550 (b)(1) by August 14, 2025 by filing a timely public disclosure describing the transactions undertaken by the Company to achieve compliance and demonstrate long-term compliance of the Minimum Stockholders' Equity Requirement, and by providing an indication of its equity following those transactions, with the option by including in the public filing a balance sheet not older than 60 days with pro forma adjustments for any significant transactions or events occurring on or before the report date; and (2) the Minimum Bid Requirement by September 8, 2025.

On August 22, 2025, the Company received a letter (the "August 2025 Letter") from Nasdaq confirming its compliance with Nasdaq Listing Rule 5550(b). Specifically, the August 2025 Letter confirmed that the Company was in compliance with both (1) the Market Value of Listing Securities standard under 5550(b)(2), which requires certain companies to maintain a market value of listed securities of at least $35 million as well as compliance with (2) the alternative stockholders' equity threshold under 5550(b)(1) or the Minimum Stockholders' Equity Requirement. Accordingly, the Company satisfied two alternative criteria under Nasdaq Listing Rule 5550.

As a result of such compliance, Nasdaq permitted the Company the remainder of the previously announced grace period to regain compliance with the $1.00 bid price rule under Nasdaq Listing Rule 5550(a)(2), through November 12, 2025. Nasdaq previously required that the Company remedy the bid price deficiency by September 8, 2025, a deadline that no longer applies.

The August 2025 Letter also provided that, solely with respect to the Equity Standard, the Company remains subject to a one-year panel monitoring period, through August 22, 2026. If, within that one-year monitoring period, the Staff determines that the Company no longer satisfies the Equity Standard (and the Company is not then in compliance with one of the alternative standards under Rule 5550(b)), the Company will not be permitted to provide the Staff with a plan of compliance and the Staff is not permitted to grant additional time to regain compliance with the Equity Standard nor will the Company be afforded an applicable cure or compliance period. Instead, the Staff will issue a delist determination letter, and the Company will have an opportunity to request a new hearing before the Nasdaq Hearings Panel, which request would stay any further action by the Staff pending the ultimate outcome of the hearing.

There can be no assurance that the Company will be able to regain compliance with the Minimum Bid Requirement or maintain compliance with the Equity Standard.

Funding and Material Cash Requirements

To date, our operating losses have been funded primarily from outside sources of invested capital from issuance of shares of our common and preferred equity, warrants, proceeds from the now-repaid in full term loan with Oxford, the margin loan facility under a line of credit with Pershing and grant funding. However, we have had, and will continue to have, an ongoing need to raise additional cash from outside sources through a combination of equity offerings, debt financings and potential collaboration, license or development agreements to fund our future clinical development programs, commercialization of CNSide, and other operations in the next twelve months from the filing of this Quarterly Report. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures, or declaring dividends. There can be no assurance that we will be able to continue to raise additional capital in the future. Our inability to raise additional cash would have a material adverse impact on our operations, implementation of our strategy and ability to maintain compliance with applicable requirements, including Nasdaq listing rules.

Our present and future funding and cash requirements will depend on many factors, including, among other things:

The accompanying condensed consolidated financial statements have been prepared assuming that we will continue to operate as a going concern, which contemplates the realization of assets and settlement of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from uncertainty related to our ability to continue as a going concern.

Cash (used in) provided by operating, investing, and financing activities for the nine months ended September 30, 2025 and 2024 is summarized as follows (in thousands):

Material Cash Obligations

Under the CPRIT Contract, we receive matching funds for approximately two-thirds of the development costs for the development of REYOBIQ for the treatment of patients with LM, subject to various funding conditions. The CPRIT Contract is effective for three years, unless otherwise terminated pursuant to the terms of the contract. CPRIT may require us to repay some or all of the disbursed CPRIT Grant proceeds (with interest not to exceed 5% annually) in the event of the early termination of the CPRIT Contract.

Other than as described above, we have no purchase commitments or long-term contractual obligations, except for lease obligations as of September 30, 2025. In addition, we have no off-balance sheet arrangements (as defined in the rules and regulations of the SEC) that have or are reasonably likely to have a current or future effect on our financial condition, changes in financial condition, revenues or expenses, results of operations, liquidity, capital expenditures or capital resources that is material to investors.

Operating activities

Net cash used in operating activities for the nine months ended September 30, 2025 of $14.5 million was primarily related to the net loss of $16.7 million and $4.7 million of changes to operating assets and liabilities, partially offset by $3.1 million of noncash financing expenses, $0.8 million of stock-based compensation expense, and $2.6 million of changes to the fair value of derivative instruments.

Net cash used in operating activities for the nine months ended September 30, 2024 of $9.3 million was primarily related to the net loss of $9.1 million and a $5.7 million change to the fair value of derivative instruments, partially offset by $3.5 million of noncash financing expenses and $0.8 million of changes to operating assets and liabilities.

Investing activities

Net cash provided by investing activities for the nine months ended September 30, 2025 of $0.2 million was primarily related to the redemption of short-term investments of $11.3 million which was partially offset by the purchase of short-term investments of $11.1 million.

Net cash used in investing activities for the nine months ended September 30, 2024 of $4.2 million was related to the purchase of Biocept assets of $0.5 million, short-term investments of $7.1 million and purchase of fixed assets of $0.1 million, partially offset by the redemption of short-term investments of $3.7 million.

Financing Activities

Net cash provided by financing activities for the nine months ended September 30, 2025 of $27.5 million was related to $19.6 million in proceeds from the sale of common stock under the Lincoln Park Purchase Agreement, $15.9 million of proceeds from sale of common stock, Pre-Funded Warrants and warrants in connection with the March 2025 Private Placement, and $3.7 million of net proceeds from the issuance of notes payable and warrants, partially offset by $3.3 million repayment on the Pershing Credit Facility, $3.7 million repayment of Notes payable, $2.3 million of costs paid to investors pursuant to the Letter Agreement, $0.2 million of costs related to the sale of common stock, and $2.3 million of financing costs related to the return and cancellation of Private Placement Shares and Pre-Funded Warrants.

Net cash provided by financing activities for the nine months ended September 30, 2024 of $6.2 million was related to net proceeds of $7.3 million from the exercise of Series B Warrants from the May 2024 Private Placement and the drawdown of $3.3 million from the Pershing Credit Facility, partially offset by the repurchase of treasury stock for approximately $0.4 million and repayment of the principle balance under the Oxford loan of $4.0 million.

Critical Accounting Policies and Significant Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires us to make estimates and assumptions that affect the reported amounts of our assets, liabilities, revenues and expenses, and that affect our recognition and disclosure of contingent assets and liabilities.

While our estimates are based on assumptions we consider reasonable at the time they were made, our actual results may differ from our estimates, perhaps significantly. If results differ materially from our estimates, we will make adjustments to our consolidated financial statements prospectively as we become aware of the necessity for an adjustment.

We believe it is important for you to understand our most critical accounting policies. Our critical accounting policies and estimates are discussed in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024 and there have been no material changes during the nine months ended September 30, 2025, other than what was disclosed in Note 2 of the accompanying condensed consolidated financial statements.