Studies of veliparib for NSCLC, breast cancer fail to meet primary endpoints
Click Here to Manage Email Alerts
Two phase 3 studies designed to evaluate veliparib in combination with chemotherapy failed to meet their primary endpoints, according to the drug’s manufacturer.
One of the randomized, double blind, multicenter studies assessed veliparib (ABT-888, AbbVie) — an investigational, oral PARP inhibitor — plus carboplatin and paclitaxel for patients with squamous non–small cell lung cancer. The other assessed the same combination in patients with triple-negative breast cancer.
"Research shows there is a role for PARP inhibitors in cancers associated with DNA repair deficits, such as those with BRCA mutations,” Gary Gordon, MD, PhD, vice president of oncology clinical development at AbbVie, said in a company-issued press release. “In these clinical trials, we wanted to explore whether a PARP inhibitor could augment chemotherapy in patients with squamous NSCLC and triple-negative breast cancer by disrupting the repair of cancer cells. Unfortunately, these data do not support the use of veliparib in combination with chemotherapy in these patients.”
The first trial included 970 patients with previously untreated metastatic or advanced squamous NSCLC. Researchers assigned patients to chemotherapy plus either veliparib or placebo.
Investigators stratified patients by smoking history as follows:
- those who had smoked within the past 12 months and had more than 100 smoking events in their lifetimes;
- those who had more than 100 smoking events in their lifetimes, with at least 12 months since the last event; and
- those who had 100 or fewer smoking events in their lifetimes.
OS among those who had smoked within the past 12 months and had more than 100 smoking events in their lifetimes served as the primary endpoint. Secondary endpoints included OS in the intent-to-treat population, PFS and overall response.
The second trial included 312 patients with early-stage triple-negative breast cancer.
Researchers randomly assigned patients to one of three regimens: veliparib plus carboplatin and standard neoadjuvant chemotherapy with paclitaxel; placebo plus carboplatin and paclitaxel; or placebo and paclitaxel alone. All patients subsequently received doxorubicin plus cyclophosphamide.
Complete pathologic response served as the primary endpoint. Secondary endpoints included breast conservation rate, OS and EFS.
Full results of these two trials will be published in peer-reviewed journals or presented at upcoming medical meetings.
Additional phase 3 studies are ongoing to evaluate veliparib for patients with nonsquamous NSCLC, BRCA1/BRCA2–mutated breast cancer and ovarian cancer.