Company additionally reports data on initial 28 evaluable patients in ongoing expansion study as well as expansion cohort dose increase based on drug exposure-response analysis

HOUSTON, Sept. 27, 2019 (GLOBE NEWSWIRE) -- Aravive, Inc. (Nasdaq: ARAV) today presented positive data from the initial 12 patients of the ongoing Phase 1b portion of the company’s Phase 1b/2 study of AVB-500 in ovarian cancer patients in a late breaking oral presentation at the European Society for Medical Oncology (ESMO) Congress in Barcelona.

The open-label, Phase 1b portion of the study of AVB-500 in patients with platinum-resistant recurrent ovarian cancer enrolled patients into two cohorts, one investigating a combination of AVB-500 with pegylated liposomal doxorubicin (PLD) and the other, a combination with paclitaxel (PAC). In both study groups, AVB-500 treatment led to early proof of concept with overall best response rate (ORR) by investigator determined RECIST v1.1 criteria and durable response in responders. AVB-500 was well tolerated with no dose limiting toxicities (DLT). The data from the initial 12 patients are summarized as follows:

• Clinical benefit [Partial Response (PR) + Stable Disease (SD)] in 7 out of 12 patients (58 percent)
• Partial responses (PR) in 5 out of 12 patients (42 percent)
  • The mean response rate in patients treated was 50 percent with AVB-500+PAC, and 33 percent with AVB-500+PLD
  • Three responders had at least 60 percent tumor regression
  • Two responders had more than 80 percent tumor regression
• The current average treatment duration for responders is 7 months and 4 of 5 patients who responded remain on study 
  • Two patients who responded have completed their chemotherapy regimen and are receiving AVB-500 alone

“Due to its aggressive nature, ovarian cancer has been particularly challenging to address therapeutically, so we are encouraged by the early positive efficacy signal,” said investigator Bradley J. Monk, M.D., professor and director of the division of gynecologic oncology at Creighton University School of Medicine at St. Joseph’s Hospital and Medical Center in Phoenix, Arizona. “This clinical study continues to support previous literature that highlights the potential for agents that can inhibit the GAS6/AXL pathway to provide new treatment options for ovarian cancer patients.”

The company continues to use Model-Informed Drug Development (MIDD) to guide selection of higher drug doses for evaluation in Phase 1b and identify the optimal drug dose for AVB-500 in the treatment of cancer.

Preliminary data from subsequent patients enrolled in the study have demonstrated an exposure-response relationship which has guided the company to study higher doses of the drug in the expansion cohort (15 mg/Kg and 20 mg/kg every two weeks). 

The following updated information from the initial 28 evaluable patients in the ongoing expansion study is reported by the company in conjunction with, but separate from, the ESMO presentation:

• AVB-500 continues to be well tolerated.
• Current response rates correlate with drug exposure:
  • Peak and trough levels after first dose of AVB-500 appear to predict anti-tumor activity. The relationship of peak drug level with response rate (PR) and clinical benefit rate (PR + SD) were statistically significant with p-values of 0.0236, 0.0337 respectively.
  • 72.7 percent of patients with peak drug level > 225 mg/L (high drug level) achieved clinical benefit (PR + SD) compared to 17.6 percent with peak drug level