Aprea Therapeutics, Inc.

Previous wording

We are targeting WEE1, a kinase that is a key regulator of multiple phases of the cell cycle. Our lead WEE1 inhibitor product candidate is APR-1051. In March 2024, our IND for APR-1051 (IND 169359) went into effect and in the second quarter of 2024 we enrolled the first patient into ACESOT-1051, our Phase 1 dose escalation study. Preliminary results provide early clinical proof-of-concept of APR-1051. On January 29, 2026, we announced the first unconfirmed partial response (uPR) observed in a patient enrolled in the ongoing Phase 1 ACESOT-1051 dose-escalation study: a patient with PPP2R1A-mutated uterine serous carcinoma, a form of endometrial cancer, treated at the 150 mg dose level of APR-1051. At the protocol-defined 8-week first imaging assessment, the patient achieved a 50% reduction in target lesion size per RECIST v1.1 criteria, along with a marked reduction in cancer antigen 125 (CA-125) levels, from 732 to 70 U/mL. CA-125 is a well-recognized tumor marker in endometrial cancer. On March 30, 2026, we announced a confirmed partial response observed in a second patient with PPP2R1A-mutated endometrial cancer, treated at the 220 mg dose level. At the first imaging assessment the patient achieved a 50% reduction in target lesion size, along with a marked decline in CA-125 from 362 at baseline to 47 U/mL, further supporting the anti-tumor activity of APR-1051. This response was subsequently confirmed at the second image assessment, with an additional 9.5% reduction in target lesion size, and a reduction in CA-125 to 40.2U/ml (from 362 U/mL at baseline). As of May 6, 2026, we observed 6 patients with stable disease in the ongoing Phase 1 ACESOT-1051 dose escalation study. We expect to report the next clinical data update from ACESOT-1051 at a medical meeting in the fourth quarter of 2026. Enrollment is accelerating ahead of this anticipated clinical catalyst, with the number of active clinical sites expanding from three to ten. We expect enrollment to reach 6 to 10 patients per month by Q4 of 2026, potentially increasing the pace of clinical data generation. Our plan is to expand enrollment in ACESOT-1051 to include at least 50 patients with uterine serous carcinoma (USC), or patients with cyclin E-overexpressing, platinum-resistant ovarian cancer (PROC). This strategy is designed to sharpen the clinical development path for APR-1051 and provide further insight into biomarker-defined patient populations most likely to benefit from WEE1 inhibition. Completion of dose escalation and backfill expansion is anticipated in the second quarter of 2027.

Current wording

We are targeting WEE1, a kinase that is a key regulator of multiple phases of the cell cycle. Our lead WEE1 inhibitor product candidate is APR-1051. In March 2024, our IND for APR-1051 (IND 169359) went into effect and in the second quarter of 2024 we enrolled the first patient into ACESOT-1051, our Phase 1 dose escalation study. Preliminary results provide early clinical proof-of-concept of APR-1051. On January 29, 2026, we announced the first unconfirmed partial response (uPR) observed in a patient enrolled in the ongoing Phase 1 ACESOT-1051 dose-escalation study: a patient with PPP2R1A-mutated uterine serous carcinoma, a form of endometrial cancer, treated at the 150 mg dose level of APR-1051. At the protocol-defined 8-week first imaging assessment, the patient achieved a 50% reduction in target lesion size per RECIST v1.1 criteria, along with a marked reduction in cancer antigen 125 (CA-125) levels, from 732 to 70 U/mL. CA-125 is a well-recognized tumor marker in endometrial cancer. On February 18, 2026, we announced a second uPR observed in a patient with PPP2R1A-mutated endometrial cancer, treated at the 220 mg dose level. At the first imaging assessment the patient achieved a 50% reduction in target lesion size, along with a marked decline in CA-125 from 362 at baseline to 47 U/mL, further supporting the anti-tumor activity of APR-1051. This response was subsequently confirmed at the second image assessment, with an additional 9.5% reduction in target lesion size, and a reduction in CA-125 to 40.2U/ml (from 362 U/mL at baseline). As of May 6, 2026, we observed 6 patients with stable disease in the ongoing Phase 1 ACESOT-1051 dose escalation study. We expect to report the next clinical data update from ACESOT-1051 at the 38 th EORTC-NCI-AACR Symposium in November 2026. Enrollment is accelerating ahead of this anticipated clinical catalyst, with the number of active clinical sites expanding from three to nine. We expect enrollment to reach 6 to 10 patients per month during the fourth quarter of 2026, potentially increasing the pace of clinical data generation. Our plan is to expand enrollment in ACESOT-1051 to include at least 50 patients with either uterine serous carcinoma (USC) or cyclin E-overexpressing, platinum-resistant ovarian cancer (PROC). This strategy is designed to sharpen the clinical development path for APR-1051 and provide further insight into biomarker-defined patient populations most likely to benefit from WEE1 inhibition. Completion of dose escalation and backfill expansion enrollment is anticipated in the second quarter of 2027. The revised timeline reflects our decision to expand enrollment to include at least 50 patients with USC or cyclin E-overexpressing PROC and the activation of additional clinical sites, and we expect it to increase research and development expenses for APR-1051 relative to our prior plans.

Previous wording

In addition, we have an early-stage program, a macrocyclic DYRK1A/B inhibitor, that we potentially could enter IND enabling studies in the fourth quarter of 2026, subject to available resources.

Current wording

In addition, we have an early-stage program, APR-1602, focused on developing macrocyclic DYRK1A/B inhibitors. We are targeting lead identification in the second quarter of 2027, subject to the availability of resources.

Previous wording

Grant revenue primarily from the National Cancer Institute of the National Institutes of Health (“NIH”) for the three months ended June 30, 2025 was $0.1 million. No grant revenue was recognized for the three months ended June 30, 2026, as the grants from NIH have been exhausted.

Current wording

Grant revenue primarily from the National Cancer Institute of the National Institutes of Health (“NIH”) for the three months ended September 30, 2025 was $1,848. No grant revenue was recognized for the three months ended September 30, 2026, as the grants from NIH have been exhausted.

Previous wording

General and administrative expenses for the three months ended June 30, 2026 were approximately $1.6 million, compared to approximately $1.6 million for the three months ended June 30, 2025.

Current wording

Research and development expenses for the three months ended September 30, 2026 were approximately $3.3 million, compared to approximately $1.6 million for the three months ended September 30, 2025. The overall increase of $1.7 million was primarily due to the following:

Previous wording

Foreign currency gain for the six months ended June 30, 2026 was $10,664 compared to a foreign currency loss of $80,927 for the six months ended June 30, 2025. The change in the foreign currency gain (loss) of $91,591 was primarily due to a strengthening of the U.S. dollar against the Swedish Krona during the six months ended June 30, 2026 as compared to the six months ended June 30, 2025. Other income was $79,000 for the six months ended June 30, 2026 and was related to the monetization of a portion of the Company’s state net operating loss carryforwards. Interest income for the six months ended June 30, 2026 and 2025 primarily consisted of interest income on our cash and cash equivalents.

Current wording

Foreign currency gain for the three months ended September 30, 2026 was $2,847 compared to a foreign currency loss of $5,691 for the three months ended September 30, 2025. The change in the foreign currency gain (loss) of $8,538 was primarily due to a strengthening of the U.S. dollar against the Swedish Krona during the three months ended September 30, 2026 as compared to the three months ended September 30, 2025. Interest income for the three months ended September 30, 2026 and 2025 primarily consisted of interest income on our cash and cash equivalents.

Previous wording

Grant revenue primarily from the NIH the six months ended June 30, 2025 was $0.3 million. No grant revenue was recognized for the six months ended June 30, 2026. The decrease in grant revenue of $0.3 million is due to recognizing less grant revenue from the NIH as these grants have been exhausted.

Current wording

Grant revenue primarily from the NIH the nine months ended September 30, 2025 was $0.3 million. No grant revenue was recognized for the nine months ended September 30, 2026. The decrease in grant revenue of $0.3 million is due to recognizing less grant revenue from the NIH as these grants have been exhausted.

Previous wording

Foreign currency gain for the three months ended June 30, 2026 was $2,953 compared to a foreign currency loss of $29,124 for the three months ended June 30, 2025. The change in the foreign currency gain (loss) of $32,077 was primarily due to a strengthening of the U.S. dollar against the Swedish Krona during the three months ended June 30, 2026 as compared to the three months ended June 30, 2025. Other income was $79,000 for the three months ended June 30, 2026 and was related to the monetization of a portion of the Company’s state net operating loss carryforwards. Interest income for the three months ended June 30, 2026 and 2025 primarily consisted of interest income on our cash and cash equivalents.

Current wording

Foreign currency gain for the nine months ended September 30, 2026 was $13,511 compared to a foreign currency loss of $86,618 for the nine months ended September 30, 2025. The change in the foreign currency gain (loss) of $100,129 was primarily due to a strengthening of the U.S. dollar against the Swedish Krona during the nine months ended September 30, 2026 as compared to the nine months ended September 30, 2025. Other income was $79,000 for the nine months ended September 30, 2026 and was related to the monetization of a portion of the Company’s state net operating loss carryforwards. Interest income for the nine months ended September 30, 2026 and 2025 primarily consisted of interest income on our cash and cash equivalents.

Previous wording

Since our inception, we have incurred significant losses on an aggregate basis. We have not yet commercialized any of our product candidates, which are in various phases of preclinical and clinical development, and we do not expect to generate revenue from sales of any products for several years, if at all. Our ability to generate product revenue sufficient to achieve profitability will depend on the successful development and eventual commercialization of one or more of our product candidates. Since 2019, our primary source of funds has been from the public sales of our common stock. As of June 30, 2026, we had cash and cash equivalents of $41.2 million. Based on our current operating plan, we believe that our existing cash and cash equivalents will enable us to fund our operating expenses and capital expenditure requirements into the first quarter of 2028.

Current wording

Since our inception, we have incurred significant losses on an aggregate basis. We have not yet commercialized any of our product candidates, which are in various phases of preclinical and clinical development, and we do not expect to generate revenue from sales of any products for several years, if at all. Our ability to generate product revenue sufficient to achieve profitability will depend on the successful development and eventual commercialization of one or more of our product candidates. Since 2019, our primary sources of funds have been the sales of our common stock and pre-funded and common stock purchase warrants in public offerings and private placements. As of September 30, 2026, we had cash and cash equivalents of $37.8 million. Based on our current operating plan, we believe that our existing cash and cash equivalents will enable us to fund our operating expenses and capital expenditure requirements into the first quarter of 2028.

Previous wording

Our net losses were $6.9 million and $7.2 million for the six months ended June 30, 2026 and 2025, respectively. As of June 30, 2026, we had an accumulated deficit of $340.5 million. These losses have resulted primarily from costs incurred in connection with research and development activities, patent investment, and general and administrative costs associated with our operations. We expect to continue to incur significant expenses and increasing operating losses for at least the next several years.

Current wording

Our net losses were $11.7 million and $10.1 million for the nine months ended September 30, 2026 and 2025, respectively. As of September 30, 2026, we had an accumulated deficit of $345.3 million. These losses have resulted primarily from costs incurred in connection with research and development activities, patent investment, and general and administrative costs associated with our operations. We expect to continue to incur significant expenses and increasing operating losses for at least the next several years.

Previous wording

On November 8, 2024, we entered into an At the Market Offering Agreement, or the 2024 ATM Agreement, with H.C. Wainright & Co., LLC, or HCW. Pursuant to the 2024 ATM Agreement and the prospectus supplement filed in connection therewith, we may, from time to time, in our sole discretion, issue and sell through HCW, acting as sales agent and/or principal, up to $3.0 million of shares of our common stock. During the six months ended June 30, 2026, we did not issue and sell any shares of common stock under the 2024 ATM Agreement. During the year ended December 31, 2025, we issued and sold 1,337,948 shares of common stock under the 2024 ATM Agreement resulting in net proceeds of approximately $1.9 million.

Current wording

On November 8, 2024, we entered into an At the Market Offering Agreement, or the 2024 ATM Agreement, with H.C. Wainright & Co., LLC, or HCW. Pursuant to the 2024 ATM Agreement and the prospectus supplement filed in connection therewith, we may, from time to time, in our sole discretion, issue and sell through HCW, acting as sales agent and/or principal, up to $3.0 million of shares of our common stock. During the nine months ended September 30, 2026, we did not issue and sell any shares of common stock under the 2024 ATM Agreement. During the year ended December 31, 2025, we issued and sold 1,337,948 shares of common stock under the 2024 ATM Agreement resulting in net proceeds of approximately $1.9 million.

Previous wording

On December 8, 2025, we entered into a securities purchase agreement with certain purchasers, or the December Purchasers, pursuant to which we agreed to issue and sell to the December Purchasers in a private placement offering exempt from registration under the Securities Act of 1933, as amended, or the Securities Act, and the December Purchasers agreed to purchase from us (i) 26,459 shares of our common stock at a purchase price of $1.165 per share, or the December 2025 Shares, (ii) pre-funded common stock purchase warrants, or the December 2025 Pre-Funded Warrants, at a purchase price of $1.164 to purchase an aggregate of up to 2,596,564 shares of our common stock at an exercise price of $0.001 per share, (iii) common stock purchase warrants to purchase up to 2,880,533 shares of our common stock at an exercise price of $1.04 per share, or the December 2025 Warrants, including this issuance of a warrant to purchase up to 257,510 shares of our common stock to the placement agent, or the Placement Agent Warrant. The December 2025 Warrants and the Placement Agent Warrant will be exercisable until the five-year anniversary of issuance. To the extent that the exercise of a December 2025 Warrant would result in the holder beneficially owning

Current wording

exempt from registration under the Securities Act of 1933, as amended, or the Securities Act, and the December Purchasers agreed to purchase from us (i) 26,459 shares of our common stock at a purchase price of $1.165 per share, or the December 2025 Shares, (ii) pre-funded common stock purchase warrants, or the December 2025 Pre-Funded Warrants, at a purchase price of $1.164 to purchase an aggregate of up to 2,596,564 shares of our common stock at an exercise price of $0.001 per share, (iii) common stock purchase warrants to purchase up to 2,880,533 shares of our common stock at an exercise price of $1.04 per share, or the December 2025 Warrants, including this issuance of a warrant to purchase up to 257,510 shares of our common stock to the placement agent, or the Placement Agent Warrant. The December 2025 Warrants and the Placement Agent Warrant will be exercisable until the five-year anniversary of issuance. To the extent that the exercise of a December 2025 Warrant would result in the holder beneficially owning greater than 4.99% (or, at the election of the holder, greater than 9.99%) of our outstanding common stock immediately following such exercise, the holder will instead receive pre-funded warrants in substantially the same form as the December 2025 Pre-Funded Warrants issued at closing. The aggregate upfront gross proceeds from the issuance of the December 2025 Shares and December 2025 Pre-Funded Warrants totaled approximately $3.1 million, before deducting placement agent fees and offering costs of approximately $0.4 million. In December 2025, we registered on Form S-3 the resale of the December 2025 Shares, the December 2025 Pre-Funded Shares and the shares underlying the December 2025 Warrants.

Previous wording

Cash used in operating activities resulted primarily from our net losses adjusted for non-cash charges and changes in components of working capital. Net cash used in operating activities was $6.0 million for the six months ended June 30, 2026 compared to $6.8 million for the six months ended June 30, 2025. The decrease in cash used in operating activities of $0.8 million was primarily attributable to a change in operating assets and liabilities of $0.6 million and a decrease in our net loss of $0.3 million, partially offset by non-cash items of $0.1 million.

Current wording

Cash used in operating activities resulted primarily from our net losses adjusted for non-cash charges and changes in components of working capital. Net cash used in operating activities was $9.8 million for the nine months ended September 30, 2026 compared to $9.9 million for the nine months ended September 30, 2025. The decrease in cash used in operating activities of $0.1 million was primarily attributable to a change in operating assets and liabilities of $1.9 million, partially offset by an increase in our net loss of $1.5 million and a decrease in non-cash items of $0.2 million.

Previous wording

Cash used in investing activities for the six months ended June 30, 2026 of $15,400 was for the purchase of property and equipment. No cash was used in or provided by investing activities for the six months ended June 30, 2025.

Current wording

Cash used in investing activities for the nine months ended September 30, 2026 of $15,401 was for the purchase of property and equipment. No cash was used in or provided by investing activities for the nine months ended September 30, 2025.

Previous wording

Net cash provided by financing activities was $32.7 million for the six months ended June 30, 2026. Cash provided by financing activities for the six months ended June 30, 2026 was attributable to the net proceeds of approximately $32.7 million, after deducting approximately $2.9 million in issuance costs, received from sales of common stock and pre-funded warrants in the January 2026 and March 2026 Private Placements.

Current wording

Net cash provided by financing activities was $33.0 million for the nine months ended September 30, 2026. Cash provided by financing activities for the nine months ended September 30, 2026 was attributable to the net proceeds of approximately $32.7 million, after deducting approximately $2.9 million in issuance costs, received from sales of common stock and pre-funded warrants in the January 2026 and March 2026 Private Placements and the exercise of 500,000 March 2026 Warrants to purchase 500,000 shares of the Company’s common stock for proceeds of $0.3 million.

Previous wording

Net cash provided by financing activities of $0.4 million for the six months ended June 30, 2025 was attributable tothe net proceeds of $0.4 million, after deducting approximately $18,000 in issuance costs, received from sales of common stock under the 2024 ATM Agreement.

Current wording

Net cash provided by financing activities of $0.8 million for the nine months ended September 30, 2025 was attributable tothe net proceeds of $0.8 million, after deducting approximately $36,000 in issuance costs, received from sales of common stock under the 2024 ATM Agreement.

Previous wording

We enter into contracts in the normal course of business with CROs and CMOs for clinical trials, preclinical research studies and testing, manufacturing and other services and products for operating purposes. These contracts do not contain any minimum purchase commitments and are cancelable by us upon prior notice of 30 days and, as a result, are not included in the table of contractual obligations above. Payments due upon cancelation consist only of payments for services provided and expenses incurred up to the date of cancelation.

Current wording

We enter into contracts in the normal course of business with CROs and CMOs for clinical trials, preclinical research studies and testing, manufacturing and other services and products for operating purposes. These contracts do not contain any minimum purchase commitments and are cancelable by us upon prior notice of 30 days and, as a result, are not included as contractual obligations. Payments due upon cancelation consist only of payments for services provided and expenses incurred up to the date of cancelation.