Veru Announces the Presentation of Updated Data From Phase 1b/2 Sabizabulin Study in Men With Metastatic Castration Resistant Prostate Cancer

Veru Inc. recently announced that updated clinical data from the positive Phase 1b/2 study of sabizabulin in 80 men with metastatic castration resistant prostate cancer who have progressed on at least one novel androgen receptor targeting agent was presented at the 2022 ASCO Genitourinary Cancers Symposium held February 17-19, 2022, in San Francisco, CA. Sabizabulin is an oral new chemical entity that represents a novel class of agents that target unique binding sites on microtubules to disrupt the cytoskeleton.

In this updated analysis of all 80 patients in the Phase 1b/2 clinical study, sabizabulin treatment demonstrated both cytotoxic and cytostatic antitumor activity. Evidence of antitumor activity was observed with PSA reductions and objective and durable tumor responses. For patients with measurable disease at baseline (n=29), the overall response rate was 20.7%. The best clinical response (stable disease or objective tumor response) in patients with measurable disease at study entry was 59% (17/29). At the time of data cut off for this presentation, 5 of the responders remain on study with the longest approaching 3 years on sabizabulin. Chronic daily dosing with sabizabulin was feasible and well tolerated with no clinically relevant neutropenia or neurotoxicity. This Phase1b/2 clinical study supports the efficacy and safety assumptions for the ongoing Phase 3 VERACITY clinical study evaluating sabizabulin in metastatic castration and androgen receptor targeting agent resistant prostate cancer prior to IV chemotherapy.

“There have been significant advances in the treatment of metastatic castration resistant prostate cancer with the use of the latest generation of novel agents that target the androgen receptor axis. Despite this, almost all patients will have tumor progression on these agents. An oral, well tolerated drug that can be utilized prior to patients moving on to intravenous chemotherapy is needed,” said Mark Markowski, MD, PhD, who presented the study. “Based upon these Phase 1b/2 data and assuming that the Phase 3 study continues to support these findings, sabizabulin appears to have the appropriate efficacy and safety to fill this unmet medical need.”

“In this further analysis, we are excited that sabizabulin continues to demonstrate long-term efficacy in patients from our Phase 1b/2 study. This may be attributed to its cytotoxic and cytostatic effects with chronic oral administration of the sabizabulin which appears to translate to long-term clinical responses,” said Mitchell S. Steiner, MD, Chairman, President and Chief Executive Officer of Veru Inc. “We are excited about the ongoing Phase 3 VERACITY study and moving sabizabulin closer to potentially providing a novel oral therapy prior to IV chemotherapy.”

In addition to the presentation on the additional analysis from the Phase 1b/2 study, a trials in progress presentation was given on the Phase 3 VERACITY study that is currently underway.

Sabizabulin is a novel oral new chemical entity that targets unique binding sites in microtubules to disrupt both the cytoskeleton. In June 2021, the Company initiated the open label, randomized (2:1), multicenter Phase 3 VERACITY clinical trial evaluating sabizabulin 32 mg versus an alternative androgen receptor targeting agent for the treatment of chemotherapy naïve men with metastatic castration resistant prostate cancer who have failed at least one androgen receptor targeting agent. The 32 mg dose formulation being studied in the VERACITY study has similar bioavailability to the 63 mg dose formulation used in the Phase 1b/2 study. The primary endpoint is median radiographic progression free survival. The Phase 3 VERACITY clinical trial is anticipated to enroll approximately 245 patients from 45 clinical centers.

Veru is an oncology biopharmaceutical company with a principal focus on developing novel medicines for the management of breast and prostate cancers. The company’s late-stage breast cancer development portfolio comprises enobosarm, a selective androgen receptor targeting agonist, and sabizabulin, a cytoskeleton disruptor.

Current studies on the two drugs include:

• Enrolling Phase 3 ARTEST study of enobosarm in androgen receptor positive, estrogen receptor positive, and human epidermal growth factor receptor two negative (AR+ ER+ HER2-) metastatic breast cancer with AR ≥ 40% expression (third-line metastatic setting), and which has been granted Fast Track designation by the FDA.
• Planned Q1 2022 Phase 3 ENABLAR-2 study of enobosarm + abemaciclib (a CDK 4/6 inhibitor) combination in AR+ ER+ HER2- metastatic breast cancer with AR ≥ 40% expression (second-line metastatic setting). The Company has entered into a clinical study collaboration and supply agreement with Lilly regarding Lilly’s supply of Verzenio (abemaciclib) for the ENABLAR-2 study.
• Planned Q1 2022 Phase 2b study of sabizabulin in AR+ ER+ HER2- metastatic breast cancer with AR < 40% expression (third-line metastatic setting).

The company has determined that patients who have ≥ 40% androgen receptor nuclei staining by immunohistochemistry in their breast cancer tissue, a measure of AR expression, are most likely to respond to enobosarm. Consequently, Veru is developing a companion diagnostic to determine a patient’s androgen receptor expression status, and has partnered with Roche/Ventana Diagnostics, a world leader in oncology companion diagnostics, which will develop and, if it is approved, commercialize the companion AR diagnostic. Veru’s late-stage prostate cancer portfolio comprises sabizabulin, VERU-100, a long-acting GnRH antagonist, and zuclomiphene citrate, an oral nonsteroidal estrogen receptor agonist.

Current studies on these drugs include:

• Enrolling Phase 3 VERACITY in metastatic castration and androgen receptor targeting agent resistant prostate cancer prior to IV chemotherapy.
• Enrolling Phase 2 dose-finding study of VERU-100 in advanced hormone-sensitive prostate cancer.
• Planned Phase 2b study of zuclomiphene citrate in men with advanced prostate cancer undergoing androgen deprivation therapy who suffer from hot flashes.

In addition, sabizabulin, which has dual antiviral and anti-inflammatory effects, is currently enrolling in a Phase 3 COVID-19 study for the treatment of hospitalized COVID-19 patients at high risk for acute respiratory distress syndrome, and which has been granted Fast Track designation by the FDA. Veru also has a commercial sexual health division – Urev, the proceeds of which help fund its drug development programs, comprised of 2 FDA approved products:

• ENTADFI (finasteride and tadalafil) capsules for oral use, a new treatment for benign prostatic hyperplasia, commercialization launch plans are underway.
• FC2 Female Condom (internal condom), for the dual protection against unplanned pregnancy and the transmission of sexually transmitted infections which is sold in the US and globally.