OBJECTIVES: Because health plans issue their own drug coverage policies, enrollees in different health plans may have differing access to the same drugs. Consequently, a merger between two health plans may affect some enrollees’ access to particular drugs. In this study, we examined changes in Aetna’s specialty drug coverage policies before and after CVS’s acquisition of Aetna in late 2018.

METHODS: We used the Tufts Medical Center Specialty Drug Evidence and Coverage Database (SPEC) to identify coverage policies issued by CVS and Aetna for 188 drug-indication pairs (e.g., infliximab for rheumatoid arthritis) pre-merger (August 2018) and two years post-merger (August 2020). At each time point, we examined CVS and Aetna’s application of the following: patient subgroup requirements (clinical criteria beyond the FDA label), step therapy protocols (requirement for patients to first try an alternative), prescriber requirements (particular type of doctor must prescribe the drug), and combination restrictions (requirement for the drug to be taken in combination with another therapy). We determined how often Aetna’s coverage policies became more generous (removal or relaxation of a coverage requirement), more restrictive (payer added a coverage requirement), or remained the same.

RESULTS: For the 188 drug-indication pairs, 14% of Aetna’s and CVS’s specialty drug coverage policies were consistent pre-merger and 82% were consistent post-merger. Aetna’s coverage policies became more generous 42% of the time, 12% became more restrictive and 46% remained unchanged. Of the 23 Aetna policies that became more restrictive, this was most often due to adjustments in patient subgroup requirements (56% of changes) and step therapy protocols (35%).

CONCLUSIONS: Our findings suggest that the CVS-Aetna merger affected patients’ access to specialty drugs. Most often, Aetna coverage became more generous, although coverage became more restrictive 12% of the time.