Tokai Pharmaceuticals has raised $23m in a Series D3 financing to support the ongoing clinical development of galeterone (TOK-001), a treatment for castration-resistant prostate cancer.

TOK-001, the company’s lead drug candidate, has completed an initial proof-of-concept Phase I clinical trial, and additional funding will advance galeterone into Phase II clinical development.

Galeterone’s novel triple mechanism of action against the growth and survival of prostate cancer cells differentiates it from other for castration-resistant prostate cancer therapies, Williams said.

The Phase I proof-of-concept clinical trial, part of the Androgen Receptor Modulation Optimized for Response (ARMOR) clinical development programme, enrolled 49 patients to evaluate dose escalating levels of galeterone and safety and reduction in prostate-specific antigen levels from baseline levels.

The financing round was led by current investors, Novartis Venture Fund and Apple Tree Partners.