- Ono to make upfront payment of approximately $16.3 million to Ribon in addition to other potential milestone payments of approximately $132 million

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Ribon Therapeutics, a clinical stage oncology company developing therapeutics targeting stress support pathways, today announced it has entered into an exclusive license agreement with Ono Pharmaceutical Co., Ltd., for the development and commercialization of RBN-2397 in Japan, South Korea, Taiwan and ASEAN countries (the �Ono Territory�). RBN-2397, Ribon�s novel, first-in-class PARP7 inhibitor, is currently in Phase 1 clinical development for the treatment of cancer.

�This agreement enables us to strategically expand our program in support of Ribon�s mission to bring therapeutics targeting stress support pathways for the treatment of cancer to as many appropriate patients as possible,� said Victoria Richon, Ph.D., President and Chief Executive Officer, Ribon Therapeutics. �We believe that RBN-2397 could serve as a meaningful intervention for the treatment of tumors with PARP7 expression, which has been shown to play a key role in cancer survival. We look forward to working with Ono, a global leader in immuno-oncology, to unlock the potential of RBN-2397 for patients in Japan, South Korea, Taiwan and ASEAN countries.�

�We are pleased to be collaborating with Ribon, a pioneer in the development of novel precision oncology drugs targeting stress support pathways�, said Gyo Sagara, President, Representative Director of Ono. �We believe that RBN-2397 could have a profound impact on patients with cancer, given the potential of the therapy�s dual mechanism to suppress tumor growth and enhance immune reaction to tumor cells. We look forward to developing RBN-2397 with Ribon by harnessing our experience and expertise in oncology.�

Under the terms of the agreement, Ribon will receive a one-time upfront payment of approximately $16.3 million from Ono. In addition, Ribon is eligible to receive up to a potential of approximately $132 million at current exchange rates based on the achievement of certain regulatory and commercial milestones, as well as tiered royalties ranging from the high single digits to low teens on net sales of RBN-2397 in the Ono Territory. In exchange, Ono will have the exclusive rights to develop and commercialize RBN-2397 in the Ono Territory. Additionally, Ono will have the right to participate in global clinical studies of RBN-2397 by bearing the costs of such studies in the Ono Territory.

Ribon retains all rights to develop and commercialize RBN-2397 worldwide outside of the Ono Territory, including the United States, the European Union and China.

About RBN-2397

RBN-2397, is an orally available small molecule inhibitor of PARP7 that we are developing for the treatment of solid tumors. PARP7 is upregulated in response to cellular stress, including genomic instability in cancers, and acts as a brake on the cellular stress response by negatively regulating the Type I interferon response. By inhibiting PARP7 in tumor cells, RBN-2397 has been shown to directly inhibit cellular proliferation and restore interferon signaling to stimulate an innate and adaptive antitumor immune response. RBN-2397 is currently in a Phase 1 dose-escalation clinical trial as a monotherapy in patients with advanced solid tumors to primarily assess safety and tolerability. PARP7 is overexpressed in a number of tumors, including squamous cell carcinoma of the lung, or SCCL, which represents approximately 30% of all non-small cell lung cancers, or NSCLC.

About Ribon Therapeutics

Ribon Therapeutics is a clinical stage biotechnology company developing first-in-class therapeutics targeting novel enzyme families activated under cellular stress conditions that contribute to disease. We are exploring novel areas of biology to develop effective treatments for patients with limited therapeutic options. Leveraging our proprietary BEACON⁺ (Blocking the Enzyme Activity Component of NAD⁺) platform, we are building a pipeline of selective, small molecule inhibitors to numerous NAD⁺-utilizing enzymes, beginning with monoPARPs, which have applications across multiple therapeutic areas. Our lead program is RBN-2397, a first-in-class PARP7 inhibitor in clinical development for the treatment of cancer. Ribon is located in Cambridge, Massachusetts. For more information visit www.RibonTx.com.

About Ono Pharmaceutical Co., Ltd.

Ono Pharmaceutical Co., Ltd., headquartered in Osaka, is an R&D-oriented pharmaceutical company committed to creating innovative medicines in specific areas. Ono focuses its research on the oncology, immunology, neurology and specialty research with high medical needs as priority areas for discovery and development of innovative medicines. For further information, please visit the company�s website at https://www.ono-pharma.com/.

Contacts

Brendan Burns

Argot Partners

212.600.1902

[email protected]