Does the color, shape or size of a generic drug affect how willing patients are to adhere to existing treatment regimens? The US Food and Drug Administration (FDA) wants to know.
FDA has long been interested in the physical attributes of drugs, and in particular generic drug products.
In December 2013, for example, it released a new guidance document, Size, Shape, and Other Physical Attributes of Generic Tablets and Capsules. In it, FDA explained that companies will need to ensure the physical differences between a generic drug and the drug it references aren't clinically meaningful.
For certain physical attributes, this line of thinking makes a certain amount of sense. If a patient if used to taking a brand-name drug that's the size of a piece of M&M candy, and is then switched to a generic drug the size of a marble, the patient might find it more difficult to take the drug, and might even stop taking it altogether.
"[We] are concerned that differences in physical characteristics (e.g., size and shape of the tablet or capsule) may affect patient compliance and acceptability of medication regimens or could lead to medication errors," FDA wrote in its guidance. "We believe these patient safety concerns are important, and we are recommending that generic drug manufacturers consider physical attributes when they develop quality target product profiles (QTPPs) for their generic product candidates," FDA added.
The intended population for a drug—the very young, the very old or the very sick—might also impact what physical forms a drug product must take, FDA said. "Although not all patient factors can be addressed through pharmaceutical design and manufacture, the physical characteristics of a product can be," FDA explained.
A New Study
FDA's interest became even more apparent in October 2014 when it proposed a study on the physical attributes of generic drugs, including one physical attribute absent from its original guidance document: color. That study has now been approved, FDA said in a Federal Register announcement on 13 May 2015.
FDA's proposed study, Survey of Pharmacists and Patients; Variations in the Physical Characteristics of Generic Drug Pills and Patients' Perceptions, would specifically look at the effects on patients when pharmacists switch generic drug suppliers.
As explained by FDA:
"When pharmacists switch generic drug suppliers, patients refilling their generic prescriptions may therefore experience changes in their drugs' appearances. These changes may result in patient confusion and concerns about the safety and effectiveness of the generic drug products. Studies indicate that patients are more likely to stop taking their generic medications when they experience a change in their drugs' physical appearances, leading to harmful clinical and public health consequences as well as increased health care costs from avoidable morbidity and mortality."
FDA said it plans to survey pharmacists and patients about their experiences with switched generic drug products "to further [FDA's] understanding of the relationship between changes in pill appearance and non-adherence to prescribed therapeutic regimens."
While FDA is unlikely to be able to require drugs to be overly similar to one another—pill appearance can actually be a protected trademark of the branded manufacturer—the survey could ultimately help to inform "strategies that pharmacists use to inform patients when the appearance of their medications change," FDA explained.
"The results of the surveys will be used to inform the development of patient education about differences in pill appearance and inform the development of education for pharmacists on strategies to counsel patients when the appearance of their medications changes."
Survey of Pharmacists and Patients; Variations in the Physical Characteristics of Generic Drug Pills and Patients' Perceptions