The early-stage biotech company, previously named FLX Bio, plans to raise up to $86 million with the IPO. It plans to trade on the Nasdaq under the ticker symbol RAPT.
RAPT Therapeutics, based in South San Francisco, filed Friday with the U.S. Securities and Exchange Commission (SEC) for an initial public offering (IPO). The early-stage biotech company, previously named FLX Bio, plans to raise up to $86 million with the IPO. It plans to trade on the Nasdaq under the ticker symbol RAPT.
It was only June 18 that the company completed a $37 million extension to its Series C financing. The extension included funds and accounts advised by T. Rowe Price Associates in addition to investors The Column Group, GV (formerly Google Ventures), Kleiner Perkins, Topspin Partners and Celgene Corporation.
“We continue to advance our pipeline of oral small molecule therapeutics, with proof-of-concept results expected in the first half of 2020 from our FLX475 program targeting multiple cancers and in mid-2020 from our RPT193 program in atopic dermatitis,” stated Brian Wong, president and chief executive officer of RAPT, at the time of the extension. “We appreciate the belief in our vision to use our immunology-based drug discovery and development engine to bring new therapeutics to patients in need of safe and effective treatment options, both in cancer and in inflammatory disease.”
In May, RAPT entered into a research deal to use Personalis’ universal cancer immunogenomics platform, ImmunoID NeXT, to study therapy-related changes in advanced cancer patients taking part in a Phase I/II clinical trial of FLX475, a CCR4 antagonist. FLX475 is being evaluated as a monotherapy or in combination with Merck’s Keytruda (pembrolizumab).
ImmunoID NeXT consolidates multiple biomarker assays, allowing for the analysis of about 20,000 genes in both DNA and RNA in a single sample. RAPT plans to compare pre- and post-treatment tumor biopsy samples to get a more comprehensive understanding of treatment-related changes in the tumors. RAPT also plans to use the technology platform to evaluate levels of several inflammation-related and immune cell type-related markers in its ongoing Phase II clinical trials of FLX475.
“Using the ImmunoID NeXT Platform for our FLX475 studies will help confirm its mechanism of action and demonstrate that inhibiting the CCR4 receptor with FLX475 blocks the migration of regulatory T-cells (Treg) into tumors,” Wong said at the time. “With this cutting-edge platform, we may be able to show that FLX475, by blocking Treg migration, decreases immune suppression and stimulates an immune response against cancer cells in the tumor microenvironment.”
RAPT has two lead programs, FLX475, which is being studied in various cancers. The second is an inflammation candidate, RPT193, which it expects to enter into the clinic in the second half of 2019. RPT193 selectively inhibits the migration of type 2 T helper cells (Th2) into allergically-inflamed tissues. Th2 cells are linked to allergic diseases such as asthma, chronic urticaria, allergic conjunctivitis, rhinosinusitis and eosinophilic esophagitis.
The company is also working to identify compounds that inhibit general control nonderepressible 2 (GCN2), a regulator of antitumor immunity and tumor cell survival.
The funds raised will be used to advance FLX475 through clinical development to commercialization, continue development of RPT193, and advanced a GCN2 inhibitor into clinical trials. It also hopes to expand its pipeline and enter into collaborations and partnerships.
