A melanoma patient treated with vemurafenib also developed leukemia temporarily, according to a case report in The New England Journal of Medicine. This drug was already known to cause squamous cell skin cancers in some people with melanomas that have BRAF mutations. Vemurafenib activates proteins called extracellular signal-regulated kinases (ERK), which are involved in cell division and can lead to cancer in cells that have RAS mutations. The leukemia in the vemurafenib-treated patient had a RAS mutation and disappeared after treatment ended. The patient’s melanoma tumors, which did not have a RAS mutation, shrank during treatment.
A new blood test could show whether melanomas are likely to return in patients who are clinically free of the disease, according to a study in the Journal of Clinical Oncology. Cancer cells that break off tumors can enter blood vessels; this test identifies three tumor cell biomarkers in blood. The researchers periodically tested blood samples of 322 patients and found those with up to one cancer biomarker were more likely to be melanoma-free compared to those with two or more cancer biomarkers (73% vs 59%). This test could show which patients would benefit from aggressive treatments.
The impressive, but still short-term, benefits of vemurafenib for melanoma patients may not justify the hefty cost to a Massachusetts Medicaid program, according to an analysis presented at an American Society of Health-System Pharmacists meeting. Vemurafenib targets the most common mutation of BRAF, which is one of the genes that is most often abnormal in melanomas. The analysis noted that vemurafenib boosted 6-month survival rates over those of the conventional chemotherapy drug dacarbazine (84% and 64%, respectively). However, vemurafenib is also more expensive than dacarbazine, with relative per patient costs estimated at $9,995 and $1,811 per month, respectively.
Treatment with vemurafenib, a drug in the BRAF inhibitor family, results in rapid tumor shrinkage in metastatic melanoma patients with the V600E BRAF mutation. The response lasts for months, but unfortunately, tumors ultimately become resistant to the treatment. Currently, vemurafenib is given as an oral dose on a daily basis. But a new study published in Nature (doi:10.1038/nature11814) suggests that a 4-weeks-on, 2-weeks-off dosing schedule may help to stave off resistance. Continue reading…