Real world experience with “generic” pomalidomide in relapsed refractory multiple myeloma

With keen interest, we read the experience shared by Scott et al. regarding the efficacy of pomalidomide in an Australian cohort of 151 patients with relapsed/refractory multiple myeloma (RRMM) treated in ‘real-world’ settings between 2010 and 2015 [1]. The authors reported an overall response rate (ORR) of 32% with a median progression-free survival (PFS) of 3.4 months and overall survival (OS) of 7.5 months. However, we would like to add that high cost and unavailability of newer anti-myeloma drugs have conventionally conferred a poor prognosis upon RRMM patients in resource-constrained settings [2,3]. Generic preparations of original formulations are commonly used in developing countries because of their low cost [4]. We would like to complement the observations of Scott et al. by sharing our experience of generic pomalidomide in RRMM since May 2017 when it became available in India. RRMM patients generally have a poor outcome because of poor performance status, cumulative burden of complications from previous therapies, and advanced disease per se [5]. Prospective randomized trials and realworld studies from developed countries have clearly demonstrated the role of pomalidomide in relapsed/ refractory myeloma [6–9]. We concur with the authors’ view that introduction of a therapy into routine clinical practice may or may not reflect the results of prospective randomized trials. Population-based studies are indispensable especially when they describe the patients who otherwise might not find representation in clinical trials. However, there are additional attributes which are unique to the developing world. Majority of the patients can’t afford the original (imported) drug formulations. Hence, it is reasonable to explore the efficacy and tolerability of generic formulations as an alternative in such patients who would otherwise be candidates for palliative care. Generic pomalidomide has been available in India since May 2017 (Pomalid launched by Natco Pharma Ltd., India). Although the same company continues to be its sole manufacturer in India, other indigenous companies have also started marketing generic pomalidomide under different brand names [Pomalong (Cipla Inc., India), Pomyelo (Intas pharmaceuticals Ltd., India), Pomahope (Abbott India Ltd., India), Pomired (Dr. Reddy’s Laboratories Ltd., India)] [10]. We used generic pomalidomide for a total of 24 RRMM patients from May 2017 to May 2018 at our institute. The choice of generic brand was decided by the patients. The median age was 63.5 years (range 3876). Ten patients had age >65 years and GFR less than 60ml/min was found in 9 patients. The patients had received a median of 4 prior therapies (range 2–7) and the median time from diagnosis to initiation of pomalidomide was 4.2 years (range 1–11.6); and, 13/24 patients (54.1%) had ECOG performance status 2. Fourteen patients (58.3%) had ISS stage 3 disease and 8 were prior autologous HSCT recipients. Seventy-five percent of patients (18 out of 24) were refractory to bortezomib as well as lenalidomide. Low platelet count (<75 10/L) before starting pomalidomide was found in 4/24 patients (16.7%). Results of FISH analysis were available for only 4 patients (1 patient had 17p deletion and 3 patients had 13q deletion). Majority of the patients (17/ 24) received pomalidomide plus dexamethasone (doublet therapy) and remaining 7 patients received a third drug [carfilzomib [3], bortezomib [2], or melphalan [2]] additionally (triplet therapy) since the beginning. Majority of the patients (16/24) received pomalidomide starting dose of 4mg daily for 21/28 days. The patients received a median of 6 cycles (range <1– 12). Five patients (20.8%) died during the study period, and 3 patients were lost to follow up. Three died because of febrile neutropenia with pneumonia before they could complete first cycle; one patient had progressive disease; and one patient with underlying coronary artery disease, who had discontinued pomalidomide after 2 weeks due to grade 4 thrombocytopenia, developed sudden cardiac arrest after receiving the first dose of daratumumab [11]. Grade 3 cytopenias were the most common serious adverse events (Table 1). Five patients (20.8%) required pomalidomide dose reduction. The overall response rate [defined as partial response (PR) or better] was 50%.