(Reuters) - Isis Pharmaceuticals Inc said it will stop developing its experimental rheumatoid arthritis (RA) drug after a mid-stage trial showed the treatment failed to significantly improve the disease symptoms when compared to a placebo.
Patients treated with the drug, called ISIS-CRPRx, had some improvements in symptoms of RA but they were not statistically significant when compared to those of patients receiving a placebo.
The treatment was developed using Isis's "antisense" technology that helps a compound bind to a specific gene in order to interrupt the production of disease-causing proteins.
The company already has regulatory approval for another drug that uses the same technology to treat a rare genetic disorder causing dangerously high levels of "bad" LDL (low-density lipoprotein) cholesterol.
The drug, Kynamro, was approved by the FDA in January.
ISIS-CRPRx was aiming to treat RA by reducing the production of C-reactive protein (CRP) -- whose levels are dramatically elevated during inflammatory disorders.
The drug is also being tested in another mid-stage trial for the treatment of atrial fibrillation - a heart rhythm disorder. Data from the trial is expected in the first half of 2014, Isis said in a statement on Monday, adding that it would continue to test the drug in other diseases.
Isis shares closed at $29.23 on Friday on the Nasdaq.
(Reporting by Esha Dey in Bangalore, additional reporting by Zeba Siddiqui; Editing by Sreejiraj Eluvangal)