Treatment of complex chronic conditions, such as rheumatoid arthritis, has led to the development of novel therapeutic drugs.1 However, these specialty medications come at a cost to the patient, and recent data indicate that higher cost-sharing is associated with reductions in the use of these drugs.
“Despite the therapeutic advances offered by many of these agents, specialty drugs have attracted payer attention because they are often accompanied by higher costs than traditional medications,” explained Jalpa A. Doshi, PhD, Division of General Internal Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, and colleagues. “Although the percentage of patients using specialty drugs is quite small—ranging from 1% to 5%—a recent report estimated specialty drug spending in the United States at $95 billion in 2013, or about 29% of total prescription drug spending.”
As part of a systematic review, the investigators sought to determine the association between patient cost-sharing and specialty drug use, as well as how it relates to health outcomes, use of nondrug medical services, and overall healthcare spending. They identified studies published in English between 1995 and 2004 using an OVID search of MEDLINE-indexed articles, and used a combination of terms, including copay, coinsurance, benefit design, as well as specialty drug, specialty pharmaceutical, and rheumatoid arthritis.
A Closer Look at Outcomes
Among studies (n = 3) that evaluated prescription abandonment as an outcome—defined as a reversal of an adjudicated claim for a newly prescribed specialty drug—Dr Doshi and colleagues found that all the studies indicated a strong association between higher cost-sharing and abandonment of all specialty drug prescriptions, compared with initiation. In particular, researchers in one study observed that approximately 25% of privately insured patients abandoned their specialty medications when the out-of-pocket costs were >$500 for anti-inflammatory biologics, compared with <5% to <6% when out-of-pocket cost claims were <$100.
Studies that evaluated initiation (n = 8) reported a negative association between cost-sharing and drug initiation, which was defined as the first-time use of a specialty drug within a study period, among patients in any given disease. In one study, investigators found that doubling the cost-sharing for rheumatoid arthritis biologics reduced initiation by 5% to 9%. Researchers in another study found that initiation of rheumatoid arthritis biologics was associated with drug benefit generosity among patients with mild-to-moderate disease activity; however, this correlation was not seen among patients with moderate or high disease activity. The investigators purported that these results indicate the possibility of disease severity impacting initiation decisions.
Nine studies pertaining to adherence were included in this review; however, Dr Doshi and colleagues noted that the relationship between how adherence related to cost-sharing was mixed. Seven studies were included about persistence—characterized by the time frame between treatment initiation and discontinuation—and discontinuation, defined as having a continuous gap of time between prescription fills, during which time the patients’ specialty drug supply has run out. Data from 6 of the 7 studies demonstrated a statistically significant increase in discontinuation associated with increased cost-sharing for ≥1 of the indications examined. In particular, data from all 3 studies on biologics for rheumatoid arthritis demonstrated associations between discontinuation and higher cost-sharing. The magnitude of the effect, however, was small, Dr Doshi and colleagues noted.
The authors of one study evaluated drug claims, and another, drug spending. Demand elasticity on the number of claims was –0.04 for rituximab, with a doubling of cost-sharing linked to an approximately 4% reduction in the number of claims. The demand elasticities for drug spending ranged from –0.07 to –0.21, with a doubling of cost-sharing for rheumatoid arthritis biologics tied to an approximately 21% reduction in total spending.
Taking Steps to Protect Patients
Although the review did not take into consideration the effect of utilization management policies, Dr Doshi and colleagues emphasize that it is crucial for payers who use these policies, or are considering implementing them, to understand their impact on specialty drug use. Furthermore, the authors noted that more data are needed to better understand the impact of the increasing use of coinsurance arrangements on specialty medication use, adherence, and outcomes.
“We have identified several gaps in the evidence base that, if addressed, would help inform future specialty drug cost-sharing policies,” Dr Doshi and colleagues concluded. “It may be appropriate in the interim to establish policies that provide additional protection for patients against aggressive cost-sharing policies for specialty drugs.”
- Doshi JA, Li P, Ladage VP, Pettit AR, Taylor EA. Impact of cost sharing on specialty drug utilization and outcomes: a review of the evidence and future directions. Am J Manag Care. 2016;22:188-197.