• Mitazalimab Phase 3 preparations underway following positive top-line results from OPTIMIZE-1 Phase 2 study in pancreatic cancer
• Positive interim data from dose escalation phase of ALG.APV-527 Phase 1 study in solid tumors expressing the tumor antigen 5T4
• New ATOR-4066 patent granted in the US
• Cash runway extended through Preferential Rights Issue

Lund, Sweden – Alligator Bioscience (Nasdaq Stockholm: ATORX)

"This quarter has been an excellent demonstration of how we are effectively and efficiently progressing our diversified pipeline of immuno-oncology assets through their various stages of development. Preparations for the Phase 3 evaluation of our lead asset mitazalimab in pancreatic cancer are fully underway following the outstanding top-line results from OPTIMIZE-1. The Phase 2 study met its primary endpoint and demonstrated the potential of mitazalimab to provide significant and sustained clinical benefit to pancreatic cancer patients. Our Neo-X-Prime® bispecific antibody ATOR-4066 received a new US patent strengthening its IP protection and also featured in a presentation at this year's AACR annual meeting, demonstrating the asset's selective activation of CD40 and opening the way to an even more targeted therapeutic approach than mitazalimab. We also reported positive interim data from the dose escalation phase of the Phase 1 study evaluating ALG.APV-527, which we are co-developing with Aptevo Therapeutics. We remain financially disciplined and our preferential rights issue ensures that we can continue to create value for our shareholders."
Søren Bregenholt, CEO of Alligator Bioscience

BUSINESS UPDATE
Mitazalimab

• On January 29, Alligator announced positive top-line results from the OPTIMIZE-1 Phase 2 trial in pancreatic cancer, demonstrating that mitazalimab in combination with mFOLFIRINOX achieved a 40.4% Overall Response Rate (ORR), a median Duration of Response (DoR) of 12.5 months, and median Overall Survival (mOS) of 14.3 months, which compares favorably to the 11.1 months mOS demonstrated by first line chemotherapies FOLFIRINOX[1] and NALIFIROX[2]. With more than half of the patients still in the study at the primary analysis, data are expected to improve even further at the 18-month survival follow-up scheduled for the middle of 2024.
• Results indicate that mitazalimab in combination with mFOLFIRINOX has the potential to deliver significant clinical benefit for pancreatic cancer patients over standard of care alone.
• Discussions with the US Food and Drug Administration (FDA) have established a clear development and approval pathway for mitazalimab in pancreatic cancer. Based on the emerging data from the OPTIMIZE-1 study, the FDA has provided additional guidance on dose characterization, and endorsed OPTIMIZE-1 as a Phase 3-enabling study. Consequently, mitazalimab can proceed directly to a global Phase 3 registration study, which Alligator is preparing to initiate in the first half of 2025, in collaboration with a commercial partner. In parallel with phase 3 preparation, Alligator has initiated the enrolment of 15 additional patients a 450 µg/kg in line with FDA’s advice.

ATOR-4066

• On January 16, Alligator announced that the United States Patent and Trademark Office (USPTO) had issued a new patent entitled "Novel peptides" which provides protection for ATOR-4066 regarding methods of treating cancer and/or a tumor using a bispecific antibody comprising the complementarity-determining regions (CDRs) of the ATOR-4066 molecule.

ALG.APV-527

• On March 7, Alligator and its partner Aptevo Therapeutics announced positive interim data from the dose escalation phase of their Phase 1 trial evaluating ALG.APV-527 for the treatment of solid tumors likely to express the tumor antigen 5T4. The results showed favorable drug exposure and confirmed the biological activity of ALG.APV-527. Signs of clinical activity were observed in patients with heavily pre-treated breast cancer. The trial is now more than 50% enrolled and a further data readout is expected in H2 2024.

RUBY

• On March 26, Alligator announced the publication of a scientific article entitled "RUBY - A tetravalent (2+2) bispecific antibody format with excellent functionality and IgG-like stability, pharmacology and developability properties" in the peer-reviewed journal mAbs.

Company

• On February 8, Alligator announced plans to restructure and reduce the current workforce by 20-25% to adjust its burn rate and secure its continued ability to invest in the development of mitazalimab and other key value drivers. When fully implemented, the restructuring is expected to reduce annual costs by approximately SEK 20 million.

Preferential Rights Issue

On February 8, Alligator announced a Preferential Rights Issue to enable continued clinical studies for candidates mitazalimab and ALG.APV-527, as well as development of pipeline candidates such as ATOR-4066. The rights issue was approved by the Extraordinary General Meeting held on March 14. On April 9, the outcome was published, reporting a total subscription of approximately 71.0 per cent. This resulted in Alligator receiving approximately SEK 107.1 million before deduction of issue costs.

Significant events after the end of the period:
AACR Presentations

• On April 8, “Mitazalimab, a potent CD40 agonist in combination with FOLFIRINOX demonstrates changes consistent with increased immune activation in TME and peripheral blood in a preclinical pancreatic cancer tumor model” was presented by Alligator at the American Association for Cancer Research (AACR) Annual Meeting in San Diego, California.
• On April 9, “ATOR-4066, a Neo-X-Prime™ bispecific antibody targeting CD40 and CEACAM5, induces tumor localized immune cell activation in preclinical in vivo tumor model” was presented by Alligator at the AACR Annual Meeting in San Diego, California.

Exercise of development option by Orion

• On April 26, Alligator announced that its partner Orion had exercised an option to develop bispecific antibodies under the second program of their initial research collaboration and license agreement entered into in 2021. This option exercise triggered the payment of an undisclosed milestone to Alligator.

FINANCIAL SUMMARY FOR Q1 2024
The financial summaries for the quarterly periods ending March 31st, 2024 and March 31st, 2023 are presented below.

The full report is attached as a PDF, and is also available on the company’s website: https://alligatorbioscience.se/en/investors/financial-reports/

Alligator will host a conference call on Monday at 3:00 p.m. CEST/ 9:00 a.m. EST for investors, analysts and media, where CEO Søren Bregenholt and CFO Marie Svensson will present and comment on the Q1 interim report, which will be followed by a Q&A session. The call will be held in English, and can be accessed through Alligator's channels on YouTube.

[1] N Engl J Med 2011 May 12;364(19):1817-25. DOI: 10.1056/NEJMoa1011923.
[2] Lancet 2023 Oct 7;402(10409):1272-1281; DOI: 10.1016/S0140-6736(23)01366-1