About Transdermal Drug Delivery

Transdermal drug delivery offers a compelling alternative to oral drug delivery and hypodermic injections. Transdermal drug delivery systems are non-invasive, can be self-administered, and often improve patient compliance. Transdermal delivery also has advantages over hypodermic injections, which can be painful and generate dangerous medical waste.

Alliqua Transdermal Drug Delivery Overview

Alliqua’s hydrogel technology can be used to deliver therapeutic compounds through the skin. Key advantages of our delivery platform include stability of form and composition, purity, reproducibility, and compatibility with various active ingredients. Within certain patient populations, transdermal drug delivery has multiple advantages over oral drug delivery or injections. Alliqua hydrogels provide a welcome texture and flexibility for the patients; their ease of administration is an added bonus.

Market Opportunity

Cumulative number of transdermal drugs approved by the FDA since the first approval in 1979.

The global transdermal and topical drug delivery market was valued at $21.5B in 2010 and is predicted to grow to $31.5B by 2015. Transdermal drug delivery accounts for more than 12% of the global drug delivery market. In the U.S., annual spending on transdermal patches exceeds $3B. Today there are more than 20 types of transdermal drug delivery patches available.

Alliqua Proof of Principle Study

In July 2013, we initiated a preclinical proof-of-principle study of an experimental hydrogel patch containing lidocaine. Topical lidocaine is thought to reduce charges of small afferent nerve fibers by blocking voltage-gated sodium channels. It is well tolerated and minimal systemic absorption occurs at the recommended dose.

Safety and tolerability of Alliqua’s lidocaine hydrogel patch were explored in an animal model. Further, the pharmacokinetic profile was analyzed to determine the amount of system absorption and local lidocaine concentration in the skin immediately beneath the patch.

Results of the study were published in October 2013 and showed that our investigational lidocaine transdermal patch compared favorably to the Lidoderm® (Lidocaine 5% patch). Our patch was able to deliver a slightly higher amount of lidocaine than Lidoderm® and was also able to reach maximum delivery within a comparable period. Further development could result in Alliqua creating a generic version of the Lidoderm® patch or providing better drug delivery resulting in 505 (b)(2) approval.

If successful, an Alliqua lidocaine patch could be used for the treatment of localized acute pain, including post-operative pain and back pain as well as pain associated with sports injuries and arthritis. As such, it would offer an interesting alternative to oral opioid medications, whose unwanted side effects include nausea, constipation and drowsiness.

Lidocaine Market Opportunity

Rate per 1000 person years, PHN defined as ≥30 days of pain.

Lidocaine patches are a large and growing market opportunity with over $1.4B in annual sales. In 1999, Lidoderm® (Lidocaine 5% patch) was approved by the FDA. In 2013, Actavis introduced a competing generic product.

Lidocaine patches are indicated for the treatment of post-herpetic neuralgia (PHN), also called post-shingles pain. PHN is the most common complication of herpes zoster (shingles), a condition that affects 1.1M individuals annually in the U.S.

Patients with PHN typically suffer persistent pain in the area where the shingles rash was present. PHN can last for weeks or months, and occasionally, for many years. Approximately 13% of shingles sufferers over 60 years experience PHN. An aging population is expected to drive demand for the product.

Sources

  • FDA Orange Book
  • UBM Canon Data Products, September 2011
  • Challenges and Opportunities in Dermal/Transdermal Delivery, Ther Deliv, July 2010
  • IMS Health, NPA Data 2005-2010. *2011/12 represents Lidoderm sales for 12 months ending March 2012, Watson press release, May 2012, **2012/13 represents Lidoderm sales for 12 months ending May 2013, Actavis press release, Sept 2013
  • MediSpan PriceRx, Wolters Kluwer (Accessed Oct 2013)
  • PubMed Search: Topical Therapies for Chronic Pain, NLM, Oct 2013