In the world of drug development, transitioning a drug from prescription use (Rx) only to over-the-counter (OTC) can be a considerable regulatory process. OTC availability can significantly broaden patient access but also poses unique regulatory challenges to safeguard consumers, develop clear instructions, enable informed patient selection, and comply with standards.
In the U.S., FDA outlines two types of switches, a full switch or a partial switch. Here are the differences:
Prescription to OTC Switch Comparison
| Feature | Full Switch | Partial Switch |
|---|---|---|
| Definition | Entire Rx product is switched to OTC for all approved indications and doses | Only some approved Rx indications are switched to OTC; others remain Rx-only |
| Regulatory Pathway | Efficacy supplement to existing NDA (21 CFR 314.70) or 505(b)(2) NDA | New NDA (typically 505(b)(2)) required |
| Labeling Requirement | Supports OTC use for all indications | Clearly differentiates Rx vs OTC indications in the labeling |
| Purpose of Consumer Studies | Demonstrate consumers can understand, self-select, and use without HCP | Demonstrate consumers can understand, self-select, and use without HCP |
| Risk of Misuse for Rx Indications | Lower (no Rx indications remain) | Higher (Prevent misuse of Rx-only indications for OTC purposes) |
When a drug company is considering the Rx to OTC switch, the initial step is to determine if the drug is appropriate for the OTC market. The FDA has criteria for determining this, which includes:
To gain FDA approval for switching a drug from prescription (Rx) to over-the-counter (OTC) status, whether through a full or partial switch, the sponsor should provide robust evidence demonstrating that consumers can appropriately self-manage the product without the supervision of a healthcare provider. This includes showing that consumers can understand the product labeling (label comprehension)3, determine whether the product is right for them (self-selection)4, use it correctly under real-world conditions (actual use)5, and that the design of the product reduces or eliminates use errors (Human Factors)6.
The FDA relies on a combination of well-designed consumer behavior studies to assess whether nonprescription marketing is appropriate and safe for the proposed indication(s). These studies are critical in establishing that the product can be used safely and effectively by the general population without medical oversight. These studies often include:
| Study Type | Purpose |
|---|---|
| Label Comprehension Study | Shows that consumers understand the Drug Facts Label (DFL). |
| Self-Selection Study | Demonstrates that consumers can determine if the product is right for them. |
| Actual Use Study | Demonstrates that consumers can use the product appropriately at home. |
| Human Factors Studies | Evaluates the capability of the user interface and design to reduce and/or mitigate use-related hazards. |
In 2024, FDA issued a final rule on a new nonprescription drug use type called Additional Condition for Nonprescription Use (ACNU). Under the ACNU, a nonprescription drug product can be marketed without a prescription as long as the sponsor develops an additional condition to ensure the user can correctly choose whether the drug is appropriate for them. Unlike the traditional full or partial Rx to OTC switch where one or more indications are completely switched to OTC use, the ACNU would allow the same drug to be sold as a prescription and a nonprescription with an ACNU at the same time.
A sponsor should also show proper actual use by users outside of the guidance of a health care provider. Examples of additional conditions include a questionnaire that helps a user determine if a product is right for them or requiring a user to watch an online tutorial before accessing the drug.
These additional conditions are developed to help users take the drug appropriately and to support a sponsor’s claims that the benefits of the drug outweigh the risks when accessed without a prescription from a healthcare provider. The goal of the ACNU is to make drugs more accessible, without compromising safety.
Innovenn’s mission is to support our clients in making safe and effective products that empower patients. Our team can help you determine if your drug is eligible for the Rx to OTC switch, advise on the regulatory path forward, conduct the labeling comprehension, self-selection, and actual use studies required for FDA submission. We have a team of experts who can help you make your Rx to OTC switch seamless. To learn more and speak to our Subject Matter Experts, please contact us.
References:
Global reach from Wisconsin HQ. Serving clients in the US, EU, UK & Canada
6410 Enterprise Lane
Suite 230
Madison, WI 53719
Sign up to get the latest industry news, insights and tips.
