Photo by Bill Branson
Vials of drugs
Cancer drug costs in the US increase substantially after launch, regardless of competition, according to a study published in the Journal of Clinical Oncology.*
Researchers studied 24 cancer drugs approved over the last 20 years and found a mean cumulative cost increase of about 37%, or 19% when adjusted for inflation.
Among drugs approved to treat hematologic malignancies, the greatest inflation-adjusted price increases were for arsenic trioxide (57%), nelarabine (55%), and rituximab (49%).
The lowest inflation-adjusted price increases were for ofatumumab (8%), clofarabine (8%), and liposomal vincristine (18%).
For this study, Daniel A. Goldstein, MD, of Emory University in Atlanta, Georgia, and his colleagues measured the monthly price trajectories of 24 cancer drugs approved by the US Food and Drug Administration. This included 10 drugs approved to treat hematologic malignancies between 1997 and 2011.
To account for discounts and rebates, the researchers used the average sales prices published by the Centers for Medicare and Medicaid Services and adjusted to general and health-related inflation rates. For each drug, the researchers calculated the cumulative and annual drug cost changes.
Results
The mean follow-up was 8 years. The mean cumulative cost increase for all 24 drugs was +36.5% (95% CI, 24.7% to 48.3%).
The general inflation-adjusted increase was +19.1% (95% CI, 11.0% to 27.2%), and the health-related inflation-adjusted increase was +8.4% (95% CI, 1.4% to 15.4%).
Only 1 of the 24 drugs studied had a price decrease over time. That drug is ziv-aflibercept, which was approved to treat metastatic colorectal cancer in 2012.
Ziv-aflibercept was launched with an annual price exceeding $110,000. After public outcry, the drug’s manufacturer, Sanofi, cut the price in half. By the end of the study’s follow-up period in 2017, the cost of ziv-aflibercept had decreased 13% (inflation-adjusted decrease of 15%, health-related inflation-adjusted decrease of 20%).
Cost changes for the drugs approved to treat hematologic malignancies are listed in the following table.
| Drug (indication, approval date, years of follow-up) | Mean monthly cost at launch | Mean annual cost change (SD) | Cumulative cost change | General and health-related inflation-adjusted change, respectively |
| Arsenic trioxide (APL, 2000, 12) | $11,455 | +6% (4) | +95% | +57%, +39% |
| Bendamustine (CLL, NHL, 2008, 8) | $6924 | +5% (5) | +50% | +32%, +21% |
| Bortezomib (MM, MCL, 2003, 12) | $5490 | +4% (3) | +63% | +31%, +16% |
| Brentuximab (lymphoma, 2011, 4) | $19,482 | +8% (0.1) | +35% | +29%, +22% |
| Clofarabine (ALL, 2004, 11) | $56,486 | +3% (3) | +31% | +8%, -4% |
| Liposomal vincristine (ALL, 2012, 3) | $34,602 | +8% (0.5) | +21% | +18%, +14% |
| Nelarabine (ALL, lymphoma, 2005, 10) | $18,513 | +6% (2) | +83% | +55%, +39% |
| Ofatumumab (CLL, 2009, 6) | $4538 | +3% (2) | +17% | +8%, -0.5% |
| Pralatrexate (lymphoma, 2009, 6) | $31,684 | +6% (4) | +43% | +31%, +21% |
| Rituximab (NHL, CLL, 1997, 12) | $4111 | +5% (0.5) | +85% | +49%, +32% |
Abbreviations: ALL, acute lymphoblastic leukemia; APL, acute promyelocytic leukemia; CLL, chronic lymphocytic leukemia; MCL, mantle cell lymphoma; MM, multiple myeloma; NHL, non-Hodgkin lymphoma; SD, standard deviation.
The researchers noted that there was a steady increase in drug costs over the study period, regardless of whether a drug was granted a new supplemental indication, the drug had a new off-label indication, or a competitor drug was approved.
The only variable that was significantly associated with price change was the amount of time that had elapsed from a drug’s launch.
This association was significant in models in which the researchers used prices adjusted to inflation (P=0.002) and health-related inflation (P=0.023). However, it was not significant when the researchers used the actual drug price (P=0.085).
*Data in the abstract differ from data in the body of the JCO paper. This article includes data from the body of the JCO paper.