Chimerix receives extended patent life for potential HBV analog

Chimerix Inc., a licensing partner of ContraVir Pharmaceuticals, received a Notice of Allowance from the United States Patent and Trademark Office for an extended patent life on its “Nucleoside Phosphonate Salts” patent, which includes CMX157, an analog intended for the treatment of hepatitis B virus infection, according to a press release.

CMX157 is a novel lipid acyclic nucleoside phosphonate that delivers high intracellular concentrations of Viread (tenofovir diphosphate, ContraVir), an antiviral agent, currently being developed for the treatment of HBV. It decreases levels of tenofovir, lowering systemic exposure and reduces the potential for renal side effects, according to the ContraVir website.

The patent covers the composition of matter for CMX157 and will extend ContraVir’s intellectual property protection of the analog through at least 2031, according to the release.

“This Notice of Allowance is a significant development for ContraVir, as it inherently increases the value of CMX157, allowing us the added time to expand the potential for this asset,” James Sapirstein, chief executive officer of ContraVir, said in the release. “The extended patent life also provides additional flexibility for the Company to pursue different combination therapies, as well as new development pathways for CMX157. We are looking to position ContraVir as a leader in the HBV space, an area that is poised for substantial further growth.”

In a randomized, blinded phase 1 clinical trial, healthy volunteers received a single dose of CMX157 (25 mg to 400 mg) or a standard dose of Viread to compare the intracellular levels of the active antiviral, tenofovir diphosphate, according to the ContraVir website. CMX157 was well tolerated and no adverse events related to the drug were reported.