Knight Therapeutics Enters into Exclusive License and Supply Agreements with Rigel Pharmaceuticals to Commercialize Fostamatinib in Latin America

Knight Therapeutics Inc. (TSX: GUD), a pan-American (ex-USA) specialty pharmaceutical company, today announced that it has entered into exclusive license and supply agreements with Rigel Pharmaceuticals granting Knight the rights to commercialize fostamatinib, an oral spleen tyrosine kinase (SYK) inhibitor, in Latin America.

Fostamatinib is commercially available in the United States under the brand name TAVALISSE ^® (fostamatinib disodium hexahydrate) and in Europe under the brand name TAVLESSE ^® for the treatment of chronic immune thrombocytopenia (ITP). Fostamatinib is also currently being studied in a Phase 3 clinical trial for the treatment of warm autoimmune hemolytic anemia (wAIHA) ¹ and in two Phase 3 clinical trials for the treatment of hospitalized patients with COVID-19. ^2,3

Under the terms of the agreement, Rigel will receive an upfront cash payment, with the potential for additional regulatory and commercial milestones, and stepped-up royalties based on tiered net sales. In return, Knight receives exclusive rights to fostamatinib in all potential indications, including chronic ITP, wAIHA, and COVID-19 in Latin America.

"This partnership represents the continued execution of our strategy of leveraging our solid platform and expertise to bring innovative medicines to our markets," said Samira Sakhia, President and CEO of Knight. "We are excited to be working with Rigel to provide access to an innovative, first-in-class treatment option to patients across Latin America with chronic ITP."

"We consider Knight to be the partner of choice in Latin America and look forward to a productive collaboration that further expands TAVALISSE's global reach to patients in need," said Raul Rodriguez, President and CEO of Rigel. "TAVALISSE is already available in several countries around the world for the treatment of chronic ITP, and we look forward to pivotal readouts from our Phase 3 clinical trials with fostamatinib in wAIHA and COVID-19."

About ITP

In patients with ITP (immune thrombocytopenia), the immune system attacks and destroys the body's own blood platelets, which play an active role in blood clotting and healing. Common symptoms of ITP are excessive bruising and bleeding. People suffering with chronic ITP may live with an increased risk of severe bleeding events that can result in serious medical complications or even death. Current therapies for ITP include steroids, blood platelet production boosters (TPO-RAs), and splenectomy. However, not all patients respond to existing therapies. As a result, there remains a significant medical need for additional treatment options for patients with ITP.

About AIHA

Autoimmune hemolytic anemia (AIHA) is a rare, serious blood disorder in which the immune system produces antibodies that lead to the destruction of the body's own red blood cells. Warm antibody AIHA (wAIHA), which is the most common form of AIHA, is characterized by the presence of antibodies that react with the red blood cell surface at body temperature. To date, there are no disease-targeted therapies approved for wAIHA, despite the unmet medical need that exists for these patients.

About COVID-19 & SYK Inhibition

COVID-19 is the infectious disease caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). SARS-CoV-2 primarily infects the upper and lower respiratory tract and can lead to acute respiratory distress syndrome (ARDS). Additionally, some patients develop other organ dysfunction including myocardial injury, acute kidney injury, shock resulting in endothelial dysfunction and subsequently micro and macrovascular thrombosis. ⁴ Much of the underlying pathology of SARS-CoV-2 is thought to be secondary to a hyperinflammatory immune response associated with increased risk of thrombosis. ⁵

SYK is involved in the intracellular signaling pathways of many different immune cells. Therefore, SYK inhibition may improve outcomes in patients with COVID-19 via inhibition of key Fc gamma receptor (FcγR) and c-type lectin receptor (CLR) mediated drivers of pathology such as pro-inflammatory cytokine release by monocytes and macrophages, production of neutrophil extracellular traps (NETs) by neutrophils, and platelet aggregation. ^{6,7 , 8 ,9} Furthermore, SYK inhibition in neutrophils and platelets may lead to decreased thrombo-inflammation, alleviating organ dysfunction in critically ill patients with COVID-19.

About Knight

Knight Therapeutics Inc., headquartered in Montreal, Canada, is a specialty pharmaceutical company focused on acquiring or in-licensing and commercializing pharmaceutical products for Canada and Latin America. Knight owns Biotoscana Investments S.A., a pan-Latin American specialty pharmaceutical company. Knight's Latin American subsidiaries operate under United Medical, Biotoscana Farma and Laboratorio LKM. Knight Therapeutics Inc.'s shares trade on TSX under the symbol GUD. For more information about Knight Therapeutics Inc., please visit the company's web site at www.gud-knight.com or www.sedar.com .

Forward-Looking Statements for Knight

This document contains forward-looking statements for Knight Therapeutics Inc. and its subsidiaries. These forward-looking statements, by their nature, necessarily involve risks and uncertainties that could cause actual results to differ materially from those contemplated by the forward-looking statements. Knight Therapeutics Inc. considers the assumptions on which these forward-looking statements are based to be reasonable at the time they were prepared but cautions the reader that these assumptions regarding future events, many of which are beyond the control of Knight Therapeutics Inc. and its subsidiaries, may ultimately prove to be incorrect. Factors and risks, which could cause actual results to differ materially from current expectations are discussed in Knight Therapeutics Inc.'s Annual Report and in Knight Therapeutics Inc.'s Annual Information Form for the year ended December 31, 2021, as filed on www.sedar.com . Knight Therapeutics Inc. disclaims any intention or obligation to update or revise any forward-looking statements whether because of new information or future events, except as required by law.

Please see www.TAVALISSE.com for full Prescribing Information.

TAVALISSE and TAVLESSE are registered trademarks of Rigel Pharmaceuticals, Inc.

Investor Contact for Knight Therapeutics Inc.:

Knight Therapeutics Inc.

References:

1. Clinicaltrials.gov: NCT03764618
2. Clinicaltrials.gov: NCT04629703
3. Clinicaltrials.gov: NCT04924660
4. Berlin DA, Gulick RM, and Martinez FJ. Severe Covid-19 . N Engl J Med 2020. DOI: https://doi.org/10.1056/NEJMcp2009575
5. Becker RC. COVID-19 Update: COVID-19 associated coagulopathy . Journal of Thrombosis and Thrombolysis May 15, 2020. DOI: https://doi.org/10.1007/s11239-020-02134-3
6. Hoepel W et al. High titers and low fucosylation of early human anti–SARS-CoV-2 IgG promote inflammation by alveolar macrophages . Science Translational Medicine 02 Jun 2021. DOI: https://www.doi.org/10.1126/scitranslmed.abf8654
7. Sung P-S and Hsieh S-L. CLEC2 and CLEC5A: Pathogenic Host Factors in Acute Viral Infections . Frontiers in Immunology December 6, 2019. DOI: https://doi.org/10.3389/fimmu.2019.02867
8. Strich J et al. Fostamatinib Inhibits Neutrophils Extracellular Traps Induced by COVID-19 Patient Plasma: A Potential Therapeutic . Journal of Infectious Disease March 15, 2021. DOI: https://doi.org/10.1093/infdis/jiaa789
9. Bye AP et al. Aberrant glycosylation of anti-SARS-CoV-2 IgG is a pro-thrombotic stimulus for platelets . BioRxiv March 26, 2021. DOI: https://doi.org/10.1101/2021.03.26.437014