Early results of treatment with carfilzomib, pomalidomide, and dexamethazone for previously treated multiple myeloma

This study examined the safety of combining a biologic therapy (pomalidomide [Pomalyst]), a targeted therapy (carfilzomib [Kyprolis]), and a steroid drug (dexamethasone [Decadron]) for relapsed or refractory multiple myeloma. Researchers reported early results on the safety and potential effectiveness of this treatment combination.

Advances in first-line treatments have improved response and survival rates among multiple myeloma patients. However, nearly all patients will relapse over time or will develop resistance to standard treatment (refractory disease). Carfilzomib is a type of targeted therapy that blocks the action of the protein proteasomes in cancer cells. Pomalidomide is a type of biologic therapy that uses the patient's immune system to fight cancer. Early studies have reported promising results with each drug for previously treated multiple myeloma. It has been suggested that their mechanisms of action could complement each other and therefore improve treatment effectiveness when combined. 

The aim of this early-phase study was to examine the safety of combining carfilzomib with pomalidomide for relapsed or refractory multiple myeloma.

32 patients with relapsed or refractory multiple myeloma were included. All patients had stopped responding to previous biologic therapy with lenalidomide (Revlimid). All patients were treated with carfilzomib and pomalidomide as well as the steroid drug dexamethasone. Treatment outcomes were followed for an average of 26.3 months.

The maximum tolerated dose of carfilzomib was 20 to 27 mg per square meter (on days 1, 2, 8, 9, 15, and 16 per 28-day treatment cycle). The maximum tolerated dose of pomalidomide was 4 mg (daily). It was 40 mg for dexamethasone (on days 1, 8, 15, and 22).

63% of patients experienced at least one serious side effect. This included low platelet (type of blood cell involved in clotting) and neutrophil (a type of white blood cell) levels, low hemoglobin (decreased red blood cells), and pneumonia. 31% of patients had at least one side effect considered severe. Low platelet and neutrophil levels as well as high creatinine levels (indicating impaired kidney function) were the most common severe side effects. Two patients experienced a fatal event following treatment, one due to pneumonia and one due to a blood clot in the lung. Eight patients had their dosage reduced and 7 discontinued treatment due to side effects.

66% of patients were deemed to have gained a clinical benefit from treatment. 50% of patients achieved at least a partial treatment response or better. Average overall survival (time from treatment until death from any cause) was 20.6 months. The 12-month overall survival rate was 67%. Average time to disease progression was 7.2 months.

Researchers concluded that the treatment combination of carfilzomib, pomalidomide and dexamethasone was well-tolerated in patients with relapsed or refractory multiple myeloma. Researchers also advised that these early results support further clinical trials of this treatment combination.