Oct 21 (Reuters) - Canadian drugmaker Tekmira Pharmaceuticals Corp has begun limited manufacturing of a drug targeting the Ebola-Guinea virus that has killed more than 4,500 people, mostly in West Africa.

The pharmaceutical company said on Tuesday that the new drug, part of its TKM-Ebola program, would be available by early December.

Tekmira's investigational new drug application to U.S. regulators for TKM-Ebola remains on partial clinical hold.

U.S.-listed shares of the company rose as much as 6 percent in trading after the company gave an update on its Ebola program.

Tekmira has completed the design of a modified RNAi (Ribonucleic acid interference) drug which particularly targets the Ebola-Guinea variant, the virus responsible for the worst Ebola outbreak on record that has hit hardest Liberia, Sierra Leone and Guinea.

Three Ebola cases have been diagnosed in the United States: Liberian Thomas Eric Duncan, who died on Oct. 8 at Texas Health Presbyterian Hospital in Dallas, and two nurses who treated him.

TKM-Ebola, an RNAi therapeutic, works by preventing the virus from replicating.

In September, U.S. and Canadian regulators authorized the use of TKM-Ebola in patients who have confirmed or suspected infections from the deadly virus.

(Reporting by Tanvi Mehta in Bangalore; Editing by Lisa Shumaker)

Our Standards: The Thomson Reuters Trust Principles.