Case Study: Chemoimmunotherapy Combination in Merkel Cell Carcinoma
Posted: Thursday, October 22, 2020
A case study published in the Journal for ImmunoTherapy of Cancer reported a complete response for a patient with Merkel cell carcinoma treated with a combination of the anti–PD-L1 monoclonal antibody avelumab, the interleukin 15–based ‘superagonist’ N-803, and low/moderate-dose nab-paclitaxel. This therapeutic combination was intended to activate the patient’s immune system.
“Advanced, metastatic Merkel cell carcinoma has been historically very difficult to treat, and immune checkpoint–refractory patients have almost no viable therapeutic options,” noted Chaitali Nangia, MD, of Chan Soon-Shiong Institute for Medicine, El Segundo, California, and colleagues.
The patient, aged 71, presented with poorly differentiated carcinoma appearing as a small cell that was initially treated without resection in February 2015, leading to a mixed response. A diagnosis of Merkel cell carcinoma was made after resection of residual disease from the abdominal wall. Disease stability was achieved after 3 months of carboplatin/etoposide treatment and maintained for 20 months. Wide excision of the Merkel cell carcinoma was performed in July 2016.
Disease progression was noted in April 2018, and avelumab treatment was initiated in May 2018. Following two rounds of avelumab therapy, the patient experienced a para-aortic lesion response but of no other masses. The addition of N-803 was implemented, and imaging 2 months into combination therapy revealed possible bone metastasis, prompting the incorporation of nab-paclitaxel. Within 1 month of starting avelumab/N-803/nab-paclitaxel treatment, the abdominal mass had decreased; within 3 months, it had nearly resolved. The patient achieved complete response at 5 months and remains on combination avelumab/N-803 maintenance therapy. The complete response has been maintained for 12 months, as of the time of study publication.
Disclosures: The study authors reported no conflicts of interest.