Braeburn Pharmaceuticals Inc., of Princeton, N.J., and Camurus AB, of Lund, Sweden, said the first patients were dosed with CAM2038, weekly and monthly subcutaneous buprenorphine injections, in a pharmacokinetic study of opioid-dependent patients with chronic pain. The primary objective of the phase II study is to assess the steady state pharmacokinetics of buprenorphine after repeated doses, including effects of injection into different subcutaneous sites. The study will also explore the effect of CAM2038 on chronic pain, along with evaluation of safety and tolerability.