Structuring Benefit Designs for Gout Treatment

Prior to the 2009 FDA approval of febuxostat, no new gout treatment options had been available in more than 40 years. Previous drugs available were allopurinol and probenecid. With the introduction of this new drug in a therapeutic class mainly composed of generic drugs, utilization management strategies, including prior authorization, step therapy, and drug coverage exclusions, may be implemented in order to contain costs.

Due to the lack of new gout treatments, no studies have been conducted to examine the benefit design and use for gout treatment, specifically in the event of a claim rejection. A recent study sought to examine the effect of utilization management methods for chronic gout treatment in this regard [J Manag Care Pharm. 2013;19(9):773-782].

The retrospective analysis examined claims data from a large, national pharmacy benefits manager with a client base that included commercial health maintenance organizations, Medicaid, Medicare Part D, and self-insurers. The study included patients aged ≥18 years who had at least 1 rejected febuxostat claim during the identification period—between March 1, 2009, and June 30, 2010.

Rejected claims were attributed to utilization management, including prior authorization, drug not covered, step therapy, quantity limits, and other limits (ie, fill limit exceeded or maximum days supply exceeded. A total of 156 possible reasons why a claim could be rejected were included.

The 2 main outcomes of interest were proportion of patients who filled febuxostat within 1 month of the rejected claim and the proportion of patients who used any chronic gout medication within 1 month of the rejected febuxostat claim. Chronic gout medications included febuxostat, allopurinol, probenecid, and colchicine/probenecid. A multivariate logistic regression model was used to assess the factors affecting patient response to a rejected claim.

A total of 1034 patients with rejected febuxostat claims were included in the study. Ninety-five percent had claims denied due to utilization management—36% due to step therapy (n=369), 25% due to lack of drug coverage (n=259), 18% due to quantity or other limits (n=183), and 16% due to prior authorization requirements (n=170)—the remaining 5% were due to other reasons unrelated to the utilization management strategies identified by the researchers.

A total of 3259 rejected claims were assessed, with 32% (n=1051) and 22% (n=711) attributed to step therapy and drug coverage, respectively.

Additionally, 474 patients (46%) filled a febuxostat prescription within 1 month following a rejected claim, while 364 patients (35%) had not filled any chronic gout medication prescription within 1 month after the rejection claim. Pre-index mean total pharmacy costs for patients who filled febuxostat were higher than for patients who did not ($1718 vs $988; P<.001). Individuals who filled febuxostat also had a higher number of pre-index drug claims (25 vs 18; P<.001).

Study limitations were referenced; this was an observational analysis using pharmacy claims data, therefore, there may be unobserved factors that could have impacted the outcomes.

The study finds that a substantial proportion of gout patients with a denied febuxostat claim received no chronic gout therapy 1 month after the rejected claim. This is important to consider when structuring future benefit designs for gout treatment.