A virus that destroys cancer cells but leaves normal cells unharmed may offer hope to those affected by squamous cell carcinoma of the lungs (SCC lung cancer), according to investigators from the Cancer Therapy & Research Center (CTRC) at the University of Texas Health Science Center at San Antonio. The CTRC has started patient enrollment in a US Phase 2 clinical trial using intravenous administration of REOLYSIN® in combination with carboplatin and paclitaxel in patients with SCC lung cancer.
REOLYSIN is an experimental treatment derived from a common virus called the reovirus. REOLYSIN directly kills many types of cancer cells and works synergistically with many approved chemotherapies and radiation.
When the reovirus enters a cancer cell, it produces thousands of copies of itself, causing the cell to burst. But the reovirus can replicate only in cancer cells with mutations along a signaling pathway in the cell called the Ras pathway, while leaving normal cells unharmed. Approximately two-thirds of all human cancers express this particular mutation and are therefore a potential target for REOLYSIN treatment.
"The study offers new hope for this group of patients with lung cancer," said Dr. Alain C. Mita, a medical oncologist and assistant professor of medicine at the CTRC at the UT Health Science Center.
The trial (REO 021) is a single arm, open-label, Phase 2 study of REOLYSIN given intravenously with paclitaxel and carboplatin every three weeks. Up to 55 patients are expected to be treated in this trial. Eligible patients include those with metastatic stage IIIB, stage IV, or recurrent squamous cell carcinoma of the lung who are chemotherapy naïve for their metastatic or recurrent cancer.
"There are significant similarities between SCC lung and SCC head and neck cancers," said Dr. Karl Mettinger, Chief Medical Officer for Calgary-based Oncolytics Biotech, the company behind REOLYSIN. "We are observing clinical benefit in a majority of our SCC head and neck cancer patients treated to date. We have seen clinical responses in metastatic lung lesions with REOLYSIN whether used as a monotherapy or in combination with paclitaxel and carboplatin, and are hopeful that this treatment combination will provide similar benefit to SCC lung cancer patients."
According to Dr. Matt Coffey, COO of Oncolytics, "This clinical study expands our interests into a variety of lung cancers. In addition to this study, we are also enrolling patients with non-small cell lung cancer (NSCLC) with K-RAS or EGFR-activated tumors in a US Phase 2 clinical trial using REOLYSIN in combination with paclitaxel and carboplatin."
The primary objective of the Phase 2 trial is to assess the antitumor effect of the treatment regimen in the study population in terms of objective response rates. The secondary objectives are to assess progression-free survival and overall survival for the treatment regimen in the study population, to determine the proportion of patients receiving the above treatment who are alive and free of disease progression at six months, and to assess the safety and tolerability of the treatment regimen in the study population.
This trial is part of a broad preclinical and clinical collaboration with the CTRC that will involve up to five, open-label, Phase 2 studies exploring the use of REOLYSIN in combination with chemotherapy for various cancer indications. Earlier this year, Oncolytics received a letter of approval from the U.K. Medicines and Healthcare products Regulatory Agency (MHRA) to conduct its Phase 3 trial examining REOLYSIN in combination with paclitaxel and carboplatin in patients with platinum-refractory head and neck cancers.
The American Cancer Society estimates that in 2009, there were approximately 219,440 new cases of lung cancer. Approximately 85% of all lung cancers are classified as NSCLC (non-squamous cell lung cancer); squamous cell carcinomas account for 25-30% of all lung cancers. Lung cancer is by far the leading cause of cancer death among both men and women. There were an estimated 159,000 deaths from lung cancer in 2009, accounting for around 28% of all cancer deaths. More people die of lung cancer than of colon, breast and prostate cancers combined.