Access to High-Cost Medications After a Cap on Monthly Out-of-Pocket Spending in California

This cross-sectional study evaluates the association of a cap on monthly out-of-pocket spending on high-cost drugs with use of these drugs and out-of-pocket spending in California in 2015 and 2016.


eMethods.
On January 1, 2016, California's ACA Marketplace (Covered California) implemented upper limits on out-of-pocket costs for expensive drugs over a certain dollar value that depended on the metal tier. The ACA organized the generosity, or actuarial value, of plans into four metal tiers, with bronze being the least and platinum being the most generous. The maximum patient out-of-pocket cost for a 30-day supply differs by metal tier, ranging from $150 for some Silver plans to $500 for Bronze plans under the new policy.
We analyzed a new data source of pharmacy claims data from private insurers offering coverage in the Covered California individual health insurance market. These data represent all pharmacy claims for nine of the eleven participating issuers; 91% (2016) to 93% (2015) of Covered California enrollees eligible for prescription drug coverage have claims included in the data. Pharmacy claims include the National Drug Code (NDC) used to identify the drug, date filled, days supplied, quantity supplied, and drug name. We identified drugs eligible for the cap by looking at claims data for 2015 and 2016, the years prior to and just after the implementation of the cap. We looked for any drug with a proxy price greater than the 30-day normalized supply threshold cost for each metal tier. (Drugs eligible for the cap are listed at the end of this file.) The proxy price and out-of-pocket spending amounts were calculated by IBM Watson, which manages these data through a contract with Covered CA. Not all insurers submit spending data (e.g. the copayments and allowed amounts) so IBM Watson imputes spending with a proprietary algorithm. Our estimates of out-of-pocket spending are based on plan-provided data where the data quality (e.g., missingness, accuracy) varies across different plan sponsors. We analyzed data We included patients continuously enrolled in the same Covered California plan for both 2015 and 2016, in order to ensure that we are able to capture their complete annual prescription drug utilization history. We further restrict the sample to patients who filled at least one capeligible drug in one or both of those years so as to characterize any changes in days supplied for those patients who had at least one fill.
We measured utilization as the number of 30-day fills of cap-eligible drugs per patient.
Adherence was measured as the total annual days supplied per patient. Finally, we captured the month in which patients hit their out-of-pocket maximum, if they reached the maximum in the year.
For each of the outcomes described above, we generated descriptive statistics. We stratify our results by the metal tier, as different metal tiers have different cost sharing caps and eligibility rules as noted above. Furthermore, there can be unobserved selection into metal tier based on health status (less healthy individuals may seek more generous plans) so we analyze the utilization by tier.
There are some limitations to this analysis. First, this is a descriptive study intended to provide an initial assessment of the effect of the cost sharing cap on utilization and costs. More detailed statistical analyses controlling for other factors that might contribute to prescription drug utilization and spending will need to be conducted to determine whether the findings shown here can be attributed to the new policy. Second, the Covered California data do not contain actual incurred costs for many of the participating insurers. This means that the proxy costs used to construct the set of cap-eligible drugs may not reflect actual spending. These costs came from Marketscan data; we were not able to assess differences between actual plan costs and the  SYPRINE  TACROLIMUS  TAFINLAR  TAGRISSO  TALTZ  TARCEVA  TARGRETIN  TASIGNA  TECFIDERA  TECFIDERA STARTER PACK  TECHNIVIE  TEMOZOLOMIDE  TETRABENAZINE  THALOMID  THYROGEN  TIVICAY  TOBI  TOBI