Abstract
BACKGROUND: Drug manufacturers claim that the purpose of financial payments to physicians is to facilitate education about new drugs. This claim suggests 2 testable hypotheses: payments should not be associated with drug revenue and payments for each drug should decline over time as physicians become educated. MATERIALS AND METHODS: We used open payments data on industry payments. We included payments for cancer drugs without generic/biosimilar competitors and used federal data sources to measure Medicare spending (a proxy for overall drug revenue) and a number of prescribers. We used generalized estimating equations (GEE) to model the drug-level association between industry payments and Medicare spending. Separately, we used GEE to estimate the change in payments with respect to the duration of time since initial FDA approval. RESULTS: The sample included 89 drugs and 361 drug-year observations. The total value of industry payments for oncology drugs increased, from $53 333 854 in 2014 to $90 343 731 in 2018. There was no association between log-transformed mean, per-physician industry payments, and per-physician Medicare spending (estimate -0.001, 95%CI, -0.005 to 0.004). Payments for individual drugs decreased over time; estimated payments in the subsequent year for a drug with mean, per-physician payments of $1000 in the index year was: $681* for drugs 0-4 years since approval, $825 for 5-9 years, and $679* for ≥10 years (*P < .05). CONCLUSIONS: Although industry-sponsored education may also serve marketing purposes, the absence of association between industry payments and Medicare spending and the decline in payments subsequent to approval are consistent with claims that industry payments function to facilitate physician education.