Targeted Checkpoint Blocking Therapies Not Yet an Effective Melanoma Treatment, Cancer Expert Says

Source: Melanoma New Today, April 2016

In a talk at the recent HemOnc Today’s Melanoma and Cutaneous Malignancies meeting, Christian Blank, group leader of the division of immunology at Netherlands Cancer Institute, presented his views of checkpoint blocking therapies. He concluded that targeted therapy is not enough to fight melanoma.

Checkpoint blocking therapies, such as anti-PD1 and anti-CTLA4, had given many late-stage melanoma patients new hope. It was believed that targeted therapy, based on the presence of certain molecules in cancer patients, would allow clinicians to choose therapies directed at these specific molecules. Studies have, however, shown that the beneficial effects are short, and checkpoint inhibition might be more complex than scientists realized.

Researchers currently believe that high levels of PD1 in a patient are indicative of treatment response, and can be viewed as a biomarker. During his March 18 talk, Dr. Blank criticized this idea, suggesting that the expression of PD1 and similar molecules is a highly dynamic affair, responsive to environmental changes such as other treatments. In his opinion, a tissue biopsy showing low levels of PD1 at one point in time is not necessarily linked to a lack of treatment response.