The dose escalation and safety trial will expand to two centres in Atlanta and Ann Arbor, subject to approval by the Institutional Review Board at each institution.
Neuralstem chairman and chief scientific officer Karl Johe said Phase II trial aims to obtain the maximum tolerated dose using the same route of administration as in Phase I that is through direct injections into the gray matter of the spinal cord.
"As a result of the excellent safety and tolerability demonstrated in Phase I, we will be able to proceed more aggressively in Phase II," Johe added.
"In Phase I, we started with just five injection sites per patient, and advanced to a maximum of 15 injections of 100,000 cells each. In Phase II, we will advance up to a maximum of 40 injections, and 400,000 cells per injection based on safety."
First 12 of the 15 patients will be administered with injections in the cervical region of the spinal cord only, where the stem cells could help preserve breathing function while three patients will receive both cervical and lumbar injections.