Pittsburgh-based Thar Pharmaceuticals Inc. is hoping to follow a similar public trajectory as one of its competitors in the complex regional pain syndrome (CRPS) space, Axsome Therapeutics Inc., which went public late last year raising about $51 million.

Thar has filed its form S-1 with the SEC looking to generate up to $50 million from an IPO. The company said it uses its Enhance technology platform to overcome the clinical limitations of existing intravenous-only therapies. Thar's lead product candidate, T121, is an orally administered, zoledronic acid DL-lysine monohydrate molecular complex, being formulated as a delayed-release composition for the management of pain associated with CRPS, which was granted an FDA orphan drug designation last year.

Zoledronic acid, an intravenous bisphosphonate branded Zometa by Basel, Switzerland-based Novartis AG, is approved for hypercalcemia in cancer and for multiple myeloma. Marketed as Reclast, also by Novartis, the product is used to treat Paget's disease and for osteoporosis in postmenopausal women, as well as men with osteoporosis. (See BioWorld Today, Oct.15, 2015.)

CRPS, which is diagnosed in approximately 80,000 people in the U.S. annually, is characterized by loss of motor function, changes in skin color and texture, bone demineralization and severe, debilitating pain, which typically exerts itself in an arm or a leg following injury or trauma.

In terms of product development the company reports that it is planning to conduct two phase III trials with approximately 150 patients in each to evaluate the safety and efficacy of T121, a non-opioid, oral formulation of zoledronic acid. If all goes according to plan the first pivotal clinical trial will start in the first quarter of next year.

Although the market for the treatment of pain associated with CRPS is small, Thar does have competitors who also have advanced their product candidates into late-stage clinical trials. In its filing, the company noted that Axsome is also working to develop an oral formulation of zoledronic acid and Grunenthal GmbH, of Aachen, Germany, is evaluating an intravenous form of neridronic acid that is in phase III trials.

Axsome has advanced its product candidate, AXS-02, for the indication into a phase III trial. As a public company its shares (NASDAQ:AXSM) are currently trading approximately 16 percent below its first day opening price of $9 on Nov. 19, 2015. The stock closed Monday at $7.58, up 4 cents.

Thar has applied to have its common stock listed on the Nasdaq Global Market under the symbol THAR, but has not yet set terms for its offering.