Skinny Labeling Allows More Drugs to Enter the Market

Skinny labeling allows more generic drugs to enter the market before patent protection ends, helping individuals to obtain treatment and facilitating lower drug prices, according to results of a study published in the Journal of Clinical Oncology.¹

Investigators studied the use of the generic version of imatinib for various indications that were excluded and included from skinny labels to determine the effectiveness of these labels for patients.¹

They gathered data on adults with commercial insurance or Medicare Advantage plans who were taking the first available generic version of imatinib between February 2016 and September 2020.¹

During that time, the generic versions had skinny labels with indications for chronic myelogenous leukemia (CML) but did not include indications for gastrointestinal stromal tumors (GISTs), because of patent protections.¹

Investigators used logistic regression to determine how the use of brand name and generic imatinib differed among individuals with a diagnosis of CML or GIST. They also adjusted for calendar month, demographic information, insurance, and prior use of brand name drugs.¹

Among 2000 individuals, approximately 47% had CML and approximately 34% had GIST. Investigators found that within 3 years of generic imatinib entering the market, approximately 90% of individuals in both the CML and GIST groups were taking the generic version, approximately 85% of individuals in the GIST arm and 88% of individuals in the CML arm.¹

Although many individuals benefited from the use of generic versions of imatinib, patients with GIST were slightly less likely to have received generic versions, even though GIST had been excluded from skinny labels.¹

However, skinny labels enabled generic versions of imatinib to be prescribed to individuals who benefit from generic drugs, whether for insurance purposes or because generics are more cost-effective.¹

High-cost drugs have been linked to a reduction in adherence that leads to poorer health outcomes, according to The Commonwealth Fund, so generic drugs are essential for individuals who might suffer because of prices.

But patent protection makes it difficult for generic medications to be readily available for individuals who would benefit from them.²

Patents cover the use of a drug for a variety of reasons, including its use in new patient populations and for different diseases. This blocks the approval of generic drugs by the FDA until the patent expires.²

Some patents, such as use patents, can last up to 20 years. The lack of market competition results in higher drug prices for brand name drugs without approved generics.²

The skinny labeling approval pathway enables generics manufactures to seek approval for generic versions of drugs, but only for the unpatented use of the comparable brand name drug.

This allows various generics to avoid patents, instead of companies having to wait for them to expire or trying to challenge the patent, which is required for generic drug applications, according to The Commonwealth Fund.²

Traditionally, labels for generic drugs must be identical to those of the brand name drug. However, skinny labeling allows manufactures to exclude information that is patented by the brand name manufacturer.²

This excludes patents about labeling, diseases, or patient populations that remain protected under use patents.²

But according to The Commonwealth Fund, the US Court of Appeals for Federal Circuit found that generic manufacturers marketing skinny label versions of drugs commit patent infringement if the drug is prescribed for indications that are patent protected by brand name manufacturers and are not part of the skinny label indications.²

This could affect skinny labeling effectiveness by blocking health care providers from prescribing skinny labeled generic drugs for indications that are patented.²

In summary, the skinny label pathway allows individuals to access generic drugs that they might not have access to otherwise. This also provides timely generic competition that could help lower the cost of the brand name drugs and improve market competition.²

For generic drugs to be the most effective for individuals who need them, it is essential that skinny labels not infringe upon patents.²

References

1. Walsh BS, Kesselheim AS, Sarpatwari A, Rome BN. Indication-Specific Generic Uptake of Imatinib Demonstrates the Impact of Skinny Labeling. J Clin Oncol. 2022;JCO2102139. doi:10.1200/JCO.21.02139

2. Walsh, BS. Skinny labeling: a pathway for timely generic drug competition. The Commonwealth Fund. Published October 19, 2021. Accessed February 21, 2022. https://doi.org/10.26099/b1c0-wn80