The first patient has been enrolled in the phase 3 VERACITY trial, which is exploring the novel oral cytoskeletal disruptor sabizabulin (VERU-111) in chemotherapy-naïve patients with metastatic castration-resistant prostate cancer (mCRPC) resistant to abiraterone acetate (Zytiga) or enzalutamide (Xtandi).1
The study (NCT04844749) has a target enrollment of 245 patients and is being conducted at more than 45 clinical sites in the United States.
“Unfortunately, advanced prostate cancer patients receiving androgen receptor targeting agents in combination with standard androgen-deprivation therapy will eventually have tumor progression. There is a significant need for new therapies with novel mechanisms of action. Sabizabulin is a novel, oral agent with provocative levels of activity and safety in early studies and we are now prospectively evaluating this agent in a phase 3 study,” Robert Dreicer, MD, lead principal investigator for the VERACITY study and deputy director, UVA Cancer Center, director of Solid Tumor Oncology, professor, Medicine: Hematology and Oncology, stated in a press release.
The VERACITY study was launched following positive phase 1b/2 data of sabizabulin in this patient population. Initial efficacy results from the phase 1b/2 trial shared at the 2021 ASCO Annual meeting showed that among 29 patients who received the recommended phase 2 dose (63 mg/daily), the objective response rate was 20.7% (n = 6), including 1 complete response and 5 partial responses.2
The open-label, phase 3 VERACITY trial is randomized patients in a 2:1 ratio to sabizabulin (32 mg daily) or the alternative antiandrogen agent not previously received by the patient (abiraterone or enzalutamide). The primary end point in progression-free survival and key secondary end points included overall survival, response, duration of response, time to chemotherapy, and pain progression.
“We are excited to begin enrolling patients in our open label phase 3 VERACITY clinical trial,” Mitchell Steiner, MD, chairman, president, and CEO of Veru Inc., the developer of sabizabulin, stated in the press release. “As we have previously reported, in the Phase 1b/2 clinical trial sabizabulin had significant evidence of tumor efficacy including PSA declines and responses as well as objective and durable tumor responses. Furthermore, sabizabulin was well tolerated without neutropenia. In fact, the safety profile of sabizabulin appears to be similar to what is reported in the package inserts for an androgen receptor targeting agent such as enzalutamide or abiraterone. If the phase 3 is successful, sabizabulin could be the next ‘go-to drug’ in the largest and growing unmet medical need in men who have metastatic castration resistant prostate cancer and who have developed progression of prostate cancer while being treated with an androgen receptor targeting agent, but prior to using IV chemotherapy.”
For expert insight on the VERACITY trial, watch Urology Times’ interview with Dr. Mark Christopher Markowski, MD, PhD, lead study author on the phase 1b/2 study of sabizabulin.
1. Veru Enrolls First Patient in Phase 3 VERACITY Clinical Trial of Sabizabulin (VERU-111) in Metastatic Castration Resistant and Androgen Receptor Targeting Agent Resistant Prostate Cancer. Published online June 25, 2021. Accessed June 25, 2021. https://bit.ly/2U0lFxJ.
2. Markowski MC, Tutrone RF, Eisenberger MA, et al. VERU-111, an oral cytoskeleton disruptor, to treat men with metastatic castration-resistant prostate cancer (mCRPC) who failed an androgen receptor targeting agent. J Clin Oncol 39, 2021 (suppl 15; abstr 5056). doi: 10.1200/JCO.2021.39.15_suppl.5056