The number of immunotherapy agents approved by the U.S. Food and Drug Administration for the treatment of patients with cancer has risen rapidly in recent years.
Naked monoclonal antibodies, such as bevacizumab, rituximab, and trastuzumab, are now approved for the treatment of various solid and hematologic cancers.
Chemolabeled antibodies, such as brentuximab vedotin, ado-trastuzumab emtansine, and the prostate cancer vaccine sipuleucel-T, add to the growing number of immunotherapies being used to combat cancer.
Positive results from various studies evaluating the use of standard immunotherapies for different cancers and novel immunotherapies were announced at the 2015 American Society of Clinical Oncology (ASCO) annual meeting in Chicago, IL.
The antiangiogenic drug bevacizumab (Avastin), which is already approved for the treatment of six cancer types, was shown to significantly increase progression-free survival (PFS) in combination with carboplatin and paclitaxel in recurrent endometrial cancer compared with carboplatin plus paclitaxel alone.
The phase 2 study showed that the addition of bevacizumab improved median PFS by more than 4 months.1 A phase 3 trial evaluating the addition of bevacizumab to letrozole as first-line endocrine therapy found that bevacizumab improved PFS by 4 months in patients with hormone receptor-positive advanced breast cancer.2
In addition, BCD-021, a bevacizumab biosimilar candidate was found to be non-inferior to Avastin in patients with non-small cell lung cancer (NSCLC) in a phase 3 trial.3 Biosimilar drugs, unlike generic drugs, do not have identical active ingredients, but are similar.
Ramucirumab (Cyramza), which is now approved for the treatment of patients with gastric, colorectal, and NSCLC, was shown to provide clinical benefit in combination with docetaxel in advanced NSCLC in the phase 3 REVEL trial, but the study had a limited number of East Asian patients who received the docetaxel 75 mg/m2 dose.
A similar phase 2 study in Japanese patients demonstrated improved clinical benefit with ramucirumab plus docetaxel 60 mg/m2 compared with docetaxel plus placebo.4
The addition of obinutuzumab (Gazyva), a CD20-directed cytolytic antibody, to bendamustine was shown to significantly improve PFS compared with bendamustine alone in patients with rituximab-refractory indolent non-Hodgkin lymphoma (NHL).5
“Obinutuzumab plus bendamustine followed by obinutuzumab maintenance represents an effective treatment option for patients with relapsed/refractory indolent NHL who are refractory to rituximab,” said Laurie Sehn, MD, MDCM, MPH, of the British Columbia Cancer Agency in Canada.
“The trial results are remarkable as this does represent the first randomized, controlled trial data that demonstrates the utility of a novel anti-CD20 monoclonal antibody in patients with rituximab-refractory lymphoma.”