A recent Spanish economic analysis indicates that glatiramer acetate injection (Copaxone) is cost-effective for the prevention of relapses in patients with established relapsing-remitting multiple sclerosis (RRMS), according to recently published results (Darbà J, et al. J Med Econ. 2014;17:215-222).
A team of investigators from Barcelona and Madrid used data from the CombiRx study to compare the cost-effectiveness of the combination of glatiramer acetate and interferon (IFN) beta-1a versus monotherapy of each of these components in patients with RRMS. The results showed that the total annual cost (2013) per patient was €13,843 (approximately $18,411) for glatiramer acetate monotherapy, compared with €15,589 (approximately $20,733) for IFN beta-1a, and €21,539 (approximately $28,646) for the combination of glatiramer plus IFN.
For their cost analysis, Rainel Sánchez-de la Rosa, MD, PhD, MSc, Medical Director and Head of Market Access, Teva Pharmaceuticals, Madrid, and colleagues used data from the CombiRx study, a 3-arm, randomized, double-blind trial comparing the efficacy of the combination of subcutaneous glatiramer 20 mg daily and intramuscular IFN beta-1a 30 mg weekly in patients with RRMS. After 36 months, the combination therapy did not significantly reduce the annual relapse rate compared with monotherapy either with glatiramer or with the IFN.
For the cost analysis, the team used a Markov model comparing three 100,000-patient hypothetical cohorts, each receiving 1 of the 3 treatment options—the combination therapy or monotherapy with 1 of the 2 therapies. The age of the patients in the CombiRx study ranged from 18 to 60 years, with an average age of 37.7 years; the average RRMS disease duration was 4.3 years; and each patient had at least 2 exacerbations in the previous 3 years. The estimated total relapse rate was 3.8 with glatiramer alone, 4.08 with the combination, and 4.18 with IFN alone.
The primary analysis, which was the cost per relapse avoided over a 10-year period, yielded total treatment costs per patient per year of €13,843 for the glatiramer monotherapy; €15,589 for the IFN monotherapy; and €21,539 for the combination of both agents. Furthermore, because glatiramer reduces the annual relapse rate more than IFN alone or the combination of both agents, glatiramer monotherapy was overall less costly and more cost-effective than the other 2 treatment options, according to the investigators.
The investigators also performed sensitivity analyses that included varying some of the parameters. For example, IFN had a higher probability of being cost-effective than glatiramer in cases where the treatment costs were less than €4000, but glatiramer was more cost-effective when treatment costs were more than €4000. The combination of both agents had a higher probability of being cost-effective up to a cost of €28,000; whereas glatiramer had the highest probability of being cost-effective compared with IFN alone from €10,000 to €28,000 overall cost, and from €28,000 versus the combination of both agents.
Furthermore, an updated analysis using 7-year follow-up data from the extension of the CombiRx study has reinforced the efficacy results of the original CombiRx study, showing that monotherapy with glatiramer continues to be superior for at least 7 years in terms of the annual relapse rate compared with the IFN monotherapy or the combination of both agents. These results, the investigators wrote, are “supportive of the cost-effectiveness results in this study.”