Background/Purpose: Prescription drugs are the third largest category of healthcare spending in the US. Four of the top five costliest drugs are biologics used for the treatment of RA. Financial relationships between physicians and pharmaceutical companies may affect prescribing . We examined the costs of drugs prescribed by rheumatologists to U.S. Medicare beneficiaries and assessed the relationship between pharmaceutical industry payments to physicians and prescribing behavior.

Methods: Three databases, Medicare part B, Medicare part D, and Open Payments were queried for non-research payments to rheumatologists between 2013-2015. Prescription drugs responsible for 80% of the total expenditure were identified for analysis (table). Prednisone was included for comparison. We calculated the mean annual drug cost per beneficiary per year; the percentage of rheumatologists who received any payments; and the median annual payment per physician per drug per year. Payments were categorized as Type 1 (intended for “key opinion leadership”) and Type 2 (intended for physicians who receive information from these experts including food and beverages, or educational materials). The relationship between industry payments and prescription drug expenditure was examined using Spearman rank correlation methods.

Results: We identified 4,932 rheumatologists who prescribed any drug(s) to Medicare beneficiaries. Etanercept and adalimumab were the most commonly prescribed non-generic drugs while repository corticotropin (rACTH) was the least prescribed. Based on the mean annual medication costs, etanercept ($741 million), adalimumab ($620 million) and infliximab ($539 million) had the highest expenditures. The annual cost of rACTH was $82 million, or $230,000 per beneficiary per year. Prednisone, the most commonly prescribed drug overall, had yearly mean annual cost of $16 million. In general, biologic costs ranged between $14,000 and $21,000 per beneficiary per year, with the exception of denosumab which was much less costly. Drugs with the lowest annual cost per beneficiary were prednisone ($42), methotrexate ($358) and hydroxychloroquine ($362). The correlation between total payments and total prescription costs per physician were low (rho<0.3), except for rACTH (rho=0.45; 95% confidence interval [CI]: 0.31, 0.57). The correlations between type 1 payments and total prescription costs were generally weaker (rho<0.2), except for rACTH (rho=0.52; 95% CI: 0.39, 0.62).

Conclusion: Payments by the pharmaceutical industry to rheumatologists are weakly associated with Medicare prescription costs. However, rACTH has a disproportionate cost relative to the number of prescribers and there was strong association between pharmaceutical payments and prescription costs related to rACTH. This finding is particularly important given the paucity of evidence and lack of clear indications for the use of rACTH.