Omeros Corporation reported the allowance by the US Patent and Trademark Office (USPTO) of an additional patent claiming the composition of OMS103HP, the company's arthroscopic PharmacoSurgery product in phase III clinical development. The patent will have a term extending into January 2020.

“This patent extends coverage for OMS103HP and adds to our established intellectual property portfolio for our PharmacoSurgery platform,” stated Gregory A Demopulos, MD, chairman and chief executive officer of Omeros. “The clinically meaningful and statistically significant improvement in postoperative knee function seen in our phase II meniscectomy trial played a role in the USPTO's decision. The drug is now in a phase III meniscectomy program and we expect data in the first half of 2012.”

Omeros is preparing additional patent applications directed to OMS103HP that would further extend its patent protection until at least 2032.

OMS103HP is Omeros' PharmacoSurgery product candidate being developed for use during arthroscopic procedures, including partial meniscectomy surgery, and was designed to provide a multimodal approach to preemptively block the inflammatory cascade induced by arthroscopy. OMS103HP is a proprietary combination of anti-inflammatory/analgesic Active Pharmaceutical Ingredients (APIs), each with well-known safety and pharmacologic profiles. Each of the APIs are components of generic, FDA-approved drugs that have been marketed in the United States as over-the-counter or prescription drug products for over 15 years and have established and well-characterized safety profiles.

In a phase II clinical trial that evaluated OMS103HP in patients undergoing partial meniscectomy surgery, OMS103HP provided clinically meaningful and significantly greater efficacy than vehicle as measured by patient-reported functional scores using the Knee Injury and Osteoarthritis Outcome Score (KOOS), passive knee flexion and visual analogue scale pain scores. The patient-reported outcomes measuring symptoms, pain, activities of daily living, sport and recreational activities and quality of life associated with the operated knee showed a sustained benefit through postoperative Day 90.

In the first quarter of 2011, Omeros announced that OMS103HP failed to meet pre-specified efficacy endpoints in a phase III clinical programme in patients undergoing arthroscopic Anterior Cruciate Ligament (ACL) reconstruction surgery. Omeros is unable to draw any conclusions about OMS103HP's effect in the phase III ACL programme due to confounding factors, and the company has no plans to conduct additional ACL reconstruction trials at this time. The primary endpoint for Omeros' meniscectomy phase III trials is different than that used in its ACL programme. Accordingly, Omeros believes that the results of its ACL program do not affect the viability of its meniscectomy programme.

Omeros is a clinical-stage biopharmaceutical company committed to discovering, developing and commercializing products focused on inflammation, coagulopathies and disorders of the central nervous system.