Jeffrey Weber, MD, PhD: Durability of a Response to Targeted Therapy Combination

How durable of a response to the targeted therapy combination would you anticipate for this patient, based on LDH levels, age, sites of disease?

For a 62-year-old patient, I would say age would fall out as a major factor that would determine durability of response. I think the more important factors are burden of disease and LDH. From the LDH point of view, the patient has a favorable durability. From the total number of sites of disease, we don’t exactly know how many, but if he has multiple pulmonary nodules and a liver nodule, probably fairly unfavorable because it’s three or fewer sites of disease that determines how durable that response is going to be. This is a patient who falls into a middle ground, and while it wouldn’t be unreasonable to have this V600K mutated patient be on BRAF/MEK for a while, most patients in this category I believe will develop resistance which is why I think eventually, perhaps sooner than later, they’ll come to the use of immunotherapy.

CASE: Metastatic Melanoma

Charles, a 62-year-old Caucasian landscaper, presented to his primary care physician with fatigue, dyspnea upon exertion, and a nonproductive cough that has lasted for 6 to 8 weeks. .

• Following a medical examination, a suspicious mole was biopsied, which resulted in a diagnosis of melanoma.
• Genetic testing revealed aBRAFV600K mutation
• PET/CT scan shows metastases to the lung and a soft tissue nodule in the liver (1.4 cm x 1.1 cm)
• LDH levels and liver function test results were normal
• The patient’s ECOG performance status was 1

Treatment was initiated with the combination of BRAF and MEK inhibitors.