Results from a Phase 2 clinical trial indicate that an investigational drug by CASI Pharmaceuticals, known as ENMD-2076, may be beneficial for patients with rare clear cell ovarian cancer (CCOC), particularly those who lack the ARID1A protein, a well-recognized indicator of negative prognosis and a potential biomarker.
The findings will be presented at the American Society of Clinical Oncology’s 2017 Annual Meeting to be held June 2-6 in Chicago, Illinois. The title of the poster presentation is, “Phase II Clinical and Molecular Trial of Oral ENMD-2076 in Clear Cell Ovarian Cancer (CCOC): A study of the Princess Margaret phase II consortium.”
ENMD-2076 is an orally administrated drug that binds and blocks the activity of the Aurora A protein and other tyrosine kinases. These enzymes are essential for normal cell division and proliferation. Exposing cancer cells to ENMD-2076 seeks to impair their growth and promote cell death. This drug also showed promise in inhibiting the growth of new blood vessels required for tumors to proliferate.
Following a Phase 1 trial in which ENMD-2076 showed promise in halting various tumor types, including ovarian, breast, liver, renal, and sarcoma, trial researchers from Princess Margaret Phase 2 Consortium explored the effects of ENMD-2076 on patients with recurrent CCOC, who often do not respond to chemotherapy.
The Phase 2 trial (NCT01914510) included 40 patients and looked at progression-free survival rates (PFS) at six months, as well as objective response rates. Two patients achieved a partial response, and 25 patients had stable disease, amounting to a disease control rate of 74%. The median progression-free survival was 3.7 months.
Because loss of expression of the ARID1A protein occurs in about half of CCOC patients, researchers stratified PFS analysis based on the presence or absence of ARID1A. Results showed that patients who lacked ARID1A expression had a mean PFS of 4.1 months, which was greater than the 3.6-month mean PFS in ARID1A-positive patients.
At the six-month mark, 20% of patients had survived and were disease free. But the six-month PFS for ARID1A was only 12%, compared to 31% in patients with loss of ARID1A.
“The identification of what appears to be an improved PFS in the patient group with ARID1A loss is encouraging and needs to be further assessed as this potential biomarker could allow for selection of patients who may potentially benefit from ENMD-2076,” Alex Zukiwski, CASI’s chief medical officer, said in a press release.
Overall, the drug was found to be safe and well tolerated. Primary adverse side effects included hypertension, nausea, and diarrhea.
“Evaluation of the clinical data and the correlative biomarker program continues and will help determine the development path in CCOC and potentially for the other tumor types for which ARID1A loss or mutation has been identified,” Zukiwski added.