Medivation Inc (NASDAQ:MDVN) announced that Phase I data from its investigational agent talazoparib, a highly-potent PARP inhibitor, was presented at the American Association for Cancer Research (AACR) Annual Meeting 2016 in New Orleans by the study’s lead investigator Zev A. Wainberg, M.D., Associate Professor of Medicine at the University of California Los Angeles (UCLA) and Co-Director of the UCLA GI Oncology Program, during a Clinical Trials Mini-Symposium. The primary objective of the study was to determine the maximum tolerated dose (MTD) of talazoparib in combination with either low-dose temozolomide or low-dose irinotecan in heavily pretreated patients with advanced malignancies.
The data from the 40 patient trial demonstrated that combination treatment with talazoparib and low-dose chemotherapy resulted in stable disease or an objective response in 23 of 40 heavily pretreated patients with a variety of advanced cancers (clinical benefit rate of 58%). Most notably, objective responses were seen in four of seven (57%) heavily pre-treated non-BRCA-mutated ovarian cancer patients when talazoparib was used in combination with either low-dose temozolomide or low-dose irinotecan. Six of seven individuals (86%) with non-BRCA ovarian cancer had clinical benefit (four partial responses and two stable disease) and had a reduction in CA 125 levels by 50% or greater.
Importantly, the overall study demonstrated responses to combination talazoparib/low-dose chemotherapy in patients with multiple tumor types in which specific deleterious mutations in certain DNA repair genes extended beyond BRCA deficiency, including one patient who did not meet the criteria of having homologous recombination deficiency (HRD). These effects may be mediated through PARP inhibition, as well as enhanced PARP trapping, which interferes with the tumor cell’s ability to replicate DNA by locking PARP molecules onto the DNA strand.
“In non-clinical studies, talazoparib has been shown to have high potency specifically against PARP 1 and 2, and antitumor effects in various solid tumors. With these new results, we now have evidence in humans that suggests talazoparib in combination with low-dose chemotherapy is active in tumors with defects in DNA repair beyond BRCA deficiency, and possibly in patients without evidence of HRD. We feel these data are consistent with talazoparib’s potent PARP trapping ability, which we believe makes talazoparib a unique and exciting product candidate with the potential to be used in combination with DNA damaging therapies across a wide variety of tumor types,” said David Hung M.D., Founder, President and Chief Executive Officer of Medivation. “With more than half of the ovarian cancer patients demonstrating an objective response, particularly in a heavily pre-treated patient population with advanced disease, these findings are encouraging and support further evaluation of the safety and efficacy of talazoparib.”
Talazoparib currently is in Phase III development for patients with locally advanced and/or metastatic breast cancer who harbor a germline BRCA1/2 mutation. It is also being studied in several investigator-sponsored trials across multiple tumor types.
The Phase I investigator-sponsored study evaluated escalating doses of talazoparib ( ≥ 0.5 mg given orally once daily) with either temozolomide ( ≥ 25 mg/m2 given orally on days 1-5; Arm A) or irinotecan ( ≥ 25 mg/m2 given by intravenous infusion every two weeks; Arm B) every 28 days in patients with advanced malignancies. Study participants ranged in age from 21 to 77 years (median: 57 years) and had received one to 15 prior chemotherapy regimens (median: 6). The primary endpoint of the study was the determination of the MTD. Secondary endpoints included pharmacokinetics, tumor response and biomarkers.
A total of 40 patients received escalating doses of talazoparib (0.5-1.0 mg) and either temozolomide or irinotecan (18 patients in Arm A and 22 in Arm B). Results showed the MTD for talazoparib was 1.0 mg. and 37.5 mg/m2 for either temozolomide or irinotecan when combined with 1.0 mg talazoparib. Partial responses were seen in four of seven (57%) germline BRCA wild type ovarian cancer patients who were platinum-resistant. Additional responses were seen in one patient each with Ewing’s Sarcoma, cervical adenocarcinoma, small cell lung cancer, and triple negative breast cancer. An association was observed between response and the presence of deleterious somatic mutations in DNA repair genes (PALB2 and RAD51D) distinct from BRCA mutations.
The most common grade 3/4 adverse events ( ≥ 5%) observed in patients treated with talazoparib plus temozolomide were neutropenia (28%), anemia (33%), and thrombocytopenia (33%). Among those treated with talazoparib plus irinotecan, the most common adverse events were thrombocytopenia (13%), anemia (27%) and neutropenia (31%). No significant pharmacokinetic interactions were observed between talazoparib and either temozolomide or irinotecan. (Original Source)
Shares of Medivation closed last Friday at $51.17, up $1.95 or 3.96%. MDVN has a 1-year high of $66.91 and a 1-year low of $26.41. The stock’s 50-day moving average is $41.28 and its 200-day moving average is $40.37.
On the ratings front, Medivation has been the subject of a number of recent research reports. In a report issued on April 15, Cowen analyst Eric Schmidt maintained a Hold rating on MDVN, with a price target of $40, which implies a downside of 21.8% from current levels. Separately, on April 6, Suntrust Robinson Humphrey’s Peter Lawson initiated coverage with a Buy rating on the stock and has a price target of $62.
According to TipRanks.com, which ranks over 7,500 financial analysts and bloggers to gauge the performance of their past recommendations, Eric Schmidt and Peter Lawson have a total average return of 16.1% and 10.5% respectively. Schmidt has a success rate of 47.2% and is ranked #158 out of 3795 analysts, while Lawson has a success rate of 58.0% and is ranked #364.
The street is mostly Bullish on MDVN stock. Out of 14 analysts who cover the stock, 8 suggest a Buy rating and 6 recommend to Hold the stock. The 12-month average price target assigned to the stock is $51.57, which represents a slight upside potential from current levels.