An agent delivery catheter which has a support member comprising at least one articulating arm having an end fixedly secured relative to the shaft and having an anchor end section opposite to the fixed end. The articulating arm is biased to pivot at the fixed end away from the shaft, to transform from a low profile configuration to a high profile configuration in which the arm extends laterally away from the shaft and the anchor end section contacts the patient's body lumen wall, to support the shaft in the body lumen during delivery of an agent, for example by injection from a needle extended from the catheter into the wall of the body lumen.