Rainier Therapeutics

About Rainier Therapeutics

Rainier Therapeutics was a privately-held, clinical-stage biotechnology company that operated in the oncology market, specifically focusing on developing treatments for bladder cancer. The company was originally founded as BioClin Therapeutics in 2010 by Stephen Lau. In September 2018, Scott Myers took over as CEO, with Lau remaining as an advisor. A significant milestone occurred in November 2018 when BioClin Therapeutics rebranded to Rainier Therapeutics, a name change intended to reflect its preparation for late-stage, pivotal studies of its main drug candidate.

The company's business was centered on the development of biologics for medical conditions with significant unmet needs. Its lead product was vofatamab, also known as B-701, a human monoclonal antibody designed to target and inhibit the activity of the fibroblast growth factor receptor 3 (FGFR3). FGFR3 is recognized as a known driver of bladder and other cancers, and vofatamab was positioned as the most advanced FGFR3-specific antagonist in clinical development at the time. The company's strategy involved evaluating vofatamab both as a monotherapy and in combination with other cancer treatments, such as pembrolizumab and docetaxel, to serve patients with locally advanced or metastatic urothelial carcinoma who had not responded to prior chemotherapy.

Rainier Therapeutics' clinical development was structured around a series of trials named FIERCE. The FIERCE-21 and FIERCE-22 studies investigated vofatamab in patients with metastatic bladder cancer, while the planned FIERCE-23 trial was intended to study the drug in early-stage bladder cancer. The company secured significant funding to support these operations. After an initial Series A round of $3 million in 2012, it raised a total of $79 million, culminating in an expanded $50 million Series B financing round in May 2018 with investors like Sofinnova Ventures, Ysios Capital, Sectoral Asset Management, and INKEF Capital. However, despite its clinical efforts and funding, Rainier Therapeutics ultimately ceased operations. In March 2021, the company went out of business, and its main asset, vofatamab, was acquired by Fusion Pharmaceuticals Inc. in July 2021.