As new immuno-oncology therapies emerge, they are proving effective against an increasingly wide range of cancers. Importantly, immunotherapies have proven effective in treating previously intractable tumors and rare cancers.
The results of continued research increasingly place immuno-oncology at the heart of new anti-cancer tactics. As researchers redouble their efforts to understand what makes the immune system most responsive to immune-boosting drugs, the future of the immuno-oncology industry looks brighter than ever.
Most recently, researchers behind two new studies found that an immuno-oncology medication effectively treated head and neck cancer that is recurrent as well as Merkel cell carcinoma, a particularly deadly type of skin cancer. These cancers can arise from either mutations in DNA or by viruses. Immunotherapy has been shown to bolster the immune system and trigger a targeted attack in cancers from either origin.
This finding is key because virus-driven cancers were not previously proven treatable by immuno-oncology techniques. Viruses, among other pathogens, result in more than 20 percent of all cancers, so the findings point to several new avenues of important research.
The Two Recent Landmark Clinical Trials
The head and neck cancer trial involved patients with metastatic or recurrent squamous cell carcinoma that had not previously responded to treatment, including platinum-based chemotherapy. No approved treatment currently exists for this demographic that has hope of extending life. However, the clinical trial, which involved the use of immunotherapy drug Opdivo, demonstrated improved survival.
The large trial included 361 patients divided into two groups. One group received Opdivo and the control was treated with chemotherapy. At the end of one year, more than a third of patients treated with Opdivo were still living, compared to only 17 percent of those in the chemotherapy group. Opdivo is now poised to become the new standard of care for a population with previously unmet needs.
The results of the Merkel cell carcinoma study are even more heartening. This particularly lethal cancer generally kills very quickly. Merkel cell carcinoma can result from exposure to ultraviolet light, but it more commonly caused by exposure to a certain common virus.
The smaller trial involved 26 patients with Merkel cell carcinoma. More than half of these patients had significant reduction in their tumors at the end of the trial. All patients were treated with Keytruda, a different immuno-oncology agent. Keytruda is designed to strengthen the immune system and help it target cancer cells. Even six months after treatment, patients who responded continued to experience good disease control, and some patients no longer have signs of the skin cancer.
The results of the Merkel cell carcinoma study encourage greater inquiry into the effectiveness of immunotherapy in the treatment of cancers caused by viruses, which is a largely unexplored area. Researchers also need to conduct more research on the mechanism that causes Keytruda to treat Merkel cell carcinoma. This will help investigators get a better idea of whether the results are durable and what maintenance treatment, if any, could be required. Regardless, both of these landmark findings have done much to spark even more excitement in the immuno-oncology sector and its role in the future standard of care for previously untreatable disease.
A Brighter Future for Cancer Care
The two new studies were joined by a third recently published report showing impressively higher survival rates among patients with advanced melanoma after receiving immunotherapy. The same drug is already approved for use in lung and kidney cancers.
These advances have created a feeling of excitement, albeit a guarded and hesitant feeling, at this year’s American Association for Cancer Research. Many years of research have looked into what drives cancer and how it interacts with the immune system. The findings of this research seem to be paying off, and the reach of this payoff continues to grow, although many questions still exist.
Hundreds of clinical trials involving cancer immunotherapies are currently ongoing in the United States. These research efforts suggest efficacy in more than two dozen types of cancer. The public has also grown excited about the prospect since former president Jimmy Carter was treated with Keytruda and radiation. The combination caused all tumors caused by his advanced melanoma, which had metastasized to the brain, to disappear to the extent that he was able to stop treatment.
However, the road ahead is still long. Scientists are working to understand exactly how the therapy works and how it can be transformed into a beneficial treatment for even more patients. Still, the excitement that exists is similar that generated in the 1960s, when chemotherapy was pioneered as a cancer treatment option.
The biggest issue still facing researchers is the fact that only a limited number of patients benefit from immunotherapy. In some trials, less than one-third of patients treated had a positive response.
To make these treatments more universal, many researchers are looking into checkpoint inhibitors, which can help make the immune system more responsive. Combination approaches also include the use of radiation, surgery, and chemotherapy along with immunotherapies.