Pfizer and Merck have advanced their clinical development programme with the initiation of two additional Phase III clinical trials to evaluate avelumab, an investigational fully human anti-PD-L1 IgG1 monoclonal antibody, in patients with ovarian and urothelial cancers.
Under the open-label, parallel group, global Javelin Ovarian 200 trial, the companies will evaluate the superiority of avelumab as monotherapy or in combination with pegylated liposomal doxorubicin (PLD) compared to PLD alone in patients with platinum-resistant / refractory ovarian cancer.
The alliance also announced that the US Food and Drug Administration has provided approval to move forward with a Phase III study of avelumab as a maintenance treatment, in the first-line setting, in patients with locally advanced or metastatic urothelial cancer. The first trial sites are expected to open shortly.
Around 550 patients from more than 190 sites in Europe, Asia and North America will be enrolled in this trial and its primary endpoint is overall survival (OS).
The second study, Phase III Javelin Bladder 100 trial, will evaluate avelumab as a maintenance treatment, in the first-line setting, in patients with locally advanced or metastatic urothelial cancer. Avelumab and best supportive care (BSC) will be compared to BSC alone.
OS is also the primary endpoint of the trial, which is expected to enroll 668 patients across more than 200 sites in 38 countries.
Pfizer Oncology Early Development, Translational and Immuno-Oncology head and vice-president Chris Boshoff said: "There are limited treatment options for women with ovarian cancer, and the prognosis for women with platinum-resistant ovarian cancer is especially poor.
"We have observed encouraging signs of early clinical activity of avelumab in patients with platinum-resistant or platinum-refractory ovarian cancer, and we hope to build on these results next year through a planned Phase III study of avelumab in combination with platinum therapy in patients with previously untreated ovarian cancer."
Avelumab also known as MSB0010718C inhibits PD-L1 interactions to potentially allow the activation of T-cells and the adaptive immune system.
Merck biopharma business head of global clinical development Alise Reicin said: "Locally advanced or metastatic urothelial cancer is another aggressive cancer, with the disease often progressing quickly following first-line treatment.
"This disease has an exceptionally high unmet need and we believe there is potential for our anti-PD-L1 antibody to be part of future treatment strategies."
Currently, the clinical development programme for avelumab includes more than 1,500 patients who have been treated across more than 15 tumour types, including breast cancer, melanoma, Merkel cell carcinoma, non-small cell lung cancer, ovarian cancer, and urothelial cancer.
The alliance began six pivotal trials, reaching its goal for 2015, with additional trials expected to be started next year.