AVI BioPharma is acquiring Ercole Biotech, its drug development partner, in a deal worth $9 million.

AVI (Nasdaq: AVII) will issue $7.5 million shares for Ercole, which is based in RTP. AVI also will assume $1.5 million in debt. AVI already is an investor in the company.

The two firms have worked together for more than a year on a drug to treat muscular dystrophy. The compound is being tested in the United Kingdom.

AVI is based in Portland, Ore.

The deal is expected to close by March 21.

Ercole is developing a new class of drugs that modulate alternative splicing — a natural gene regulatory mechanism. Ercole believes its technology is applicable to several major diseases, include cancer, inflammatory diseases and cardiovascular disorders.