Lund, Sweden, April 27, 2020 ? Alligator Bioscience (Nasdaq Stockholm: ATORX),?announces that the company today presents the status of the ongoing Phase I clinical trial with the bispecific drug candidate ATOR-1015 developed as tumor-directed therapy for metastatic cancer. The presentation will take place at the AACR (American Association for Cancer Research) Annual Meeting, which this year is being held digital for the first time.

This far, doses of 400 mg (about 6 mg/kg) have been evaluated in the ongoing study and the current dosing is 600 mg (about 10 mg/kg). 18 patients with varying cancer forms (colon cancer, eye melanoma, pancreatic cancer, ovarian cancer, gallbladder cancer, gastric cancer and skin cancer) have been treated and evaluated in terms of safety. ATOR-1015 has so far been well tolerated.

?We are very proud and happy that our study has been selected for presentation. The promising results so far demonstrate that ATOR-1015 can be administered safely. ATOR-1015 has the potential to be at least as effective as today?s available treatment for these patients, but with significantly fewer side effects,? said Per Norl?n, CEO of Alligator Bioscience.

The adverse events in the study were generally mild and transient, all of grade 1 or 2 (on a scale of 1?5). The most common adverse events were infusion-related reactions (five patients). No serious immune-related or dose-limiting adverse events have been reported.

The presentation with the title ?A first-in-human phase 1 study in patients with advanced and/or refractory solid malignancies to evaluate the safety of ATOR-1015, a CTLA-4 x OX40 bispecific antibody? will be held by Charlotte Russell, Chief Medical Officer at Alligator Bioscience. The presentation is available through the link below between 9:00 a.m. ? 6:00 p.m. EDT (3 p.m.-12 a.m. CEST) today and will also be available on the company website?http://www.alligatorbioscience.com.?https://www.abstractsonline.com/pp8/#!/9045/presentation/10644

For further information, please contact: Cecilia Hofvander, Director Investor Relations & Communications Phone +46?46 540 82 06 E-mail:?cecilia.hofvander@alligatorbioscience.com

This information is such information as Alligator Bioscience AB (publ) is obliged to make public pursuant to the EU Market Abuse Regulation. The information was submitted for publication, through the agency of the contact person set out above, at 6:01 a.m.?CEST on April 27, 2020.

About the ATOR-1015 Phase I study The Phase I study with ATOR-1015 is a dose escalation study in patients with metastatic cancer (NCT03782467). The primary endpoint of the study is to investigate the safety and tolerability of ATOR-1015 and to determine the recommended dose for subsequent Phase II studies. The first patient was dosed in March 2019 and results are expected during the second half of 2020. Following the establishment of the maximum tolerable dose or recommended dose for Phase II, further clinical development of ATOR-1015 is planned, primarily for the treatment of metastatic skin cancer.

Due to the Covid-19 pandemic, most, but not all, participating clinics have made a temporary halt in the recruitment of new patients. Alligator Bioscience is in close dialogue with all parties in order to resume patient recruitment at full speed as soon as possible. The company follows the clinics? decisions and evaluates appropriate measures to minimize any delays. At this stage, it is too early to estimate whether the slower recruitment will affect the timeline for 2020 and for the longer term.

About ATOR-1015 ATOR-1015, wholly owned by Alligator, is a bispecific CTLA-4 antibody developed as tumor targeted immunotherapy with increased capacity for killing regulatory T cells. ATOR-1015 binds to two different immune receptors ? the checkpoint receptor CTLA-4 and the co-stimulatory receptor OX40.?The immune activation is increased in areas where both target molecules are expressed at high levels, notably in the tumor microenvironment, which can lead to reduced side effects.

About Alligator Bioscience Alligator Bioscience AB is a clinical-stage biotechnology company developing tumor-directed immuno-oncology antibody drugs. Alligator?s growing pipeline includes five lead clinical and preclinical drug candidates: mitazalimab, ATOR-1015, ATOR-1017, ALG.APV-527 (co-developed with Aptevo Therapeutics Inc.) and AC101 (in clinical development by Shanghai Henlius Biotech Inc.). Alligator?s shares are listed on Nasdaq Stockholm (ATORX). The Company is headquartered in Lund, Sweden. For more information, please visit?http://www.alligatorbioscience.com.