By Mary Welch
Adolor Corp. signed an agreement worth up to $48 million with SmithKline Beecham plc for the development and commercial rights to ADL 2-1294, a topical dermal therapy for the treatment of inflammatory pain, itching and other indications.
Adolor, based in Malvern, Pa., will retain the prescription rights for certain topical dermal indications as well as rights outside the topical dermal field, including ophthalmic, mucosal, post-surgical and intra-articular indications.
London-based SmithKline Beecham (SKB) obtained worldwide rights (excluding Korea) for the prescription and over-the-counter (OTC) rights to ADL 2-1204 (loperamide).
Although specifics of the deal were not disclosed, Adolor said it will receive up to $48 million in development milestone payments and an up-front payment consisting of a cash and equity investment. Adolor also will receive royalties based on product sales. SKB will be responsible for all development costs associated with the licensed products.
In late 1997, Adolor signed a licensing deal with Kwang Dong Pharmaceutical Co., of Seoul, South Korea, to develop ADL 2-1294 in that country for dermal pain.
"This is our first [significant] deal and we're proud that SmithKline Beecham saw the value in our compound," said John Farrar, president and CEO of Adolor. "It's a new use for an old compound."
Adolor's approach to pain management differs from many traditional opioid therapeutics because Adolor's compounds work only on the surface and don't penetrate into the brain. Adolor develops compounds that activate only peripheral opioid receptors but result in a significant reduction in hyperalgesic pain or itch.
ADL 2-1294, a topical peripheral opioid anti-hyperalgesic, represents a family of newly patented formulations of loperamide hydrochloride for skin, eye and other applications where it can be applied locally to inflamed tissues. The drug's active ingredient is loperamide, which is the active ingredient in the over-the-counter anti-diarrhea medication Imodium A-D.
Loperamide is safe but had been misunderstood, Farrar said. "For simple inflammation pain models, it doesn't have an addictive narcotic element to it because the compound does not cross the blood-brain barrier," he said. "It's the only non-DEA-scheduled opiate drug in existence - bar none. It's absolutely unique."
The compound had been in Phase II trials to provide relief of hyperalgesia, or severe inflammatory pain and pruritis. Farrar doesn't know if SKB will take over those trials or start its own. "It may be that SmithKline Beecham will try to develop a more specific formulation for the indications they want," he said.
In fact, ADL 2-1294 formulations were being developed by Adolor for pruritic skin conditions, such as poison ivy, atopic dermatitis, eczema and psoriasis. Those formulations are covered under the SKB deal.
Adolor, for its part, may continue those Phase II trials for indications following surgical procedures. "We may pursue it for indications for use after you have a wart removed or a chemical or laser peel. We retained the rights for uses like that."
Adolor also retained the rights for ADL 2-1294, but in a different formulation, for an ophthalmic indication, now in Phase II trials. If approved, it would be used for inflammatory pain associated with corneal hyperalgesia associated with corneal abrasions, surgical/laser keratotomy and pterygium. Clinical studies are planned for early next year for an injectable formulation to treat pain associated with arthroscopic and other surgical procedures.
Farrar said the company is starting licensing talks with potential partners for some of those indications.
Founded in 1994, Adolor has another compound, ADL 8-2698, in Phase II trials to reverse narcotic-induced constipation, and ADL 10-0101 in Phase I trials for the treatment of post-surgical pain.