Update on Approval History for Passive Skin Patches (1979-2020)

In 2015, I published a paper titled “Transdermal Product Development in the Age of QbD”. In that paper, I provided an accounting of all the prescription-only, FDA-approved drug patches as of 2015. Since a number of years have passed since then, I thought it would be appropriate to audit/update those data and revisit my assertion that novel patches (APIs not previously delivered to/through the skin) are approved by the FDA at a rate of about 1 patch every other year((A concept I hinted at as early as 2011 and first presented formally in “The Role and Implications of QbD in the Topical/Transdermal Drug Development Process”, AAPS Webinar, February 2014.)).

In the process of revisiting these data, I omitted active patches (iontophoretic and self-heating patches) and I also added several non-OTC, passive patches I had overlooked that were approved by the FDA, but not launched or never widely available. Consequently, the more narrowly focused count of prescription-only, passive patches approved by the FDA by 2015 was 63 (five more than the 58 I claimed at the time) which works out to about 7 months between approvals from 1979 to 2015.

In the five-and-a-half years since the original paper was published, 21 more patches were approved bringing the total to 84 as of April 2021((I worked on 16 of these projects or about 1 in 5.)). This means the average time between approvals since 1979 is now 1 month less than it was just 5½ years ago and the average lag between approvals since 2015 is only 100 days!

The chart below shows the updated graph for all passive patch approvals. Those marked in red are the projects in which I participated.

The original paper also contained a plot of the novel patch approvals (i.e., the subset of approvals for which the API was first delivered by a topical/transdermal patch). At the time of publication in 2015, I noted 24 novel patches with an approval rate of about one patch every other year. After double-checking the data, I found there were only 20 novel, passive patches approved as of 2015 which gives a rate of 1.8 years (22 months) between approvals from 1979 to 2015 (still about 1 patch every other year.) Since 2015, only one novel patch has been approved by the FDA (Secuado, asenapine transdermal system, 10/15/2019), but that is enough to continue the trend.

As of this writing, there are 21 novel, passive patches approved by the FDA over the last 42 years so the historic rate is still EXACTLY 2 years/patch.

The chart below shows all the novel API patches plotted at their respective approval dates and a broken line showing the slope of one approval every 2.02 years.

These data, of course, consider only the US market which is still (I believe) the largest market for commercial pharmaceuticals and is often the focus for product development even for developers outside the USA. Nevertheless, these data give us confidence that the field is just as active as it ever was–even as we approach half a century.

Ken Miller

Perspectives in Percutaneous Penetration-La Grande Motte, France

I’m heading for the South of France next week for the 15th International Conference on Perspectives in Percutaneous Penetration.

I look forward to this meeting for a number of reasons, but mostly because this is the meeting where I met, and continue to meet, the world’s most prominent researchers. (Some of whom I met at the 2nd PPP more than a quarter century ago). We’ve all learned a lot about the skin since then, but we’re still learning and that’s the point of the meeting.

If you’re going to be at the PPP in La Grande Motte next week, stop by and see me in the expo. I’d love to hear a little about what you’re up to and I might even be able to make a suggestion or two.

Au revoir!



In Case You Missed It…

The Transdermal and Intradermal Drug Delivery Systems conference in Philadelphia was a great success.

Thanks to the sponsors, organizers and attendees for making this a diverse and fascinating event and I can’t wait for the next one!

In case you missed the conference, you can check out my slides at the link below.

Novel Patch Designs & Technologies

Be sure to check out the other speakers and talks from the brochure and follow Pharma Ed Resources for information on the next one!

I’ll be there!

Did you know?

Did you know most transdermal patches…

…are no thicker than a human hair?

…last longer than the pills they replace?

…with fewer side effects?

…no moving or electronic parts?

…and cost only pennies to manufacture?

Want to know more? Let’s talk about it.

Time is running out!

Transdermal and Intradermal Drug Delivery Systems, 2015 Advanced Design, Development, and Delivery of Skin-Mediated Therapies and Vaccines

May 11-12 at the Racquet Club of Philadelphia. Early Bird registration ends 3/20/15 (this Friday!).

Check out the brochure on the Pharma ED Resources website and register here or contact me directly to see if you’re eligible for a discount.

Upcoming Conference

Here’s a heads up as you make your plans for the new year:

Pharma ED Resources Inc. is organizing
Transdermal and Intradermal Drug Delivery Systems, 2015 Advanced Design, Development, and Delivery of Skin-Mediated Therapies and Vaccines

May 11-12 at the Racquet Club of Philadelphia (that’s only 3 months from now!)

They’ve assembled an impressive line-up of speakers and I’m really looking forward to it.

On Monday afternoon, I will be chairing a panel discussion on regulatory considerations and on Tuesday morning, I will be talking about novel patch designs.

Check out the brochure on the Pharma ED Resources website and register here or contact me directly to see if you’re eligible for a discount.

See you there!

Got Questions?

What kind of companies need ISYN?

  • Want to know whether a compound could be formulated into a topical or transdermal product?

I can help you.

  • Are you considering licensing a compound for topical or transdermal administration?

I can help you.

  • Even if your company has a top-rated topical/transdermal development team, but is simply overwhelmed…

I can help  you.

Got questions? Find the answers!

I’m on-board to take you where YOU want to go.

ISYN Consulting “I can take you there.”


Another Satisfied Client

A senior executive from a leading pharmaceutical company had this to say about their experience with ISYN Consulting


We were completely satisfied!  More specifically, we appreciated:

  • Your thoroughness in reviewing documentation
  • Your willingness to “cross-over” from CMC to clinical and preclinical areas
  • Your strong follow-up and control competencies in terms of producing slide decks, distilling information down to a review friendly format and your willingness to discuss broader topics around patch development, such as CMO selection choices
  • The COGs feedback we got was impressive – very detailed and relevant, helping us to ballpark certain decisions at key times
  • Your support with ideas around irritancy studies was very helpful
  • Your experience regarding historical patch development was useful to the team


We DO know where to find you…and I hope to be in fact looking for you soon.