Defense lawyers for hemophilia expert Takeshi Abe, 84, on Wednesday said their client was innocent of professional negligence resulting in death, claiming he prescribed HIV-tainted blood coagulants to a patient in 1985 due to limited knowledge of the product's danger at the time.

In Abe's final trial hearing at the Tokyo District Court, his counsel claimed that prosecutors, who are demanding a three-year prison term, ignored the limitations of medical science and focused only on their tragic consequences.

Abe, former vice president of Teikyo University and a former top hemophilia authority, instructed subordinate doctors to administer unheated blood products to the hemophiliac in 1985, resulting in the patient's death from AIDS in 1991, according to the indictment.

This is the third criminal trial over the 1980s HIV debacle in which at least 1,430 hemophiliacs and other blood transfusion recipients contracted the virus and in which doctors, bureaucrats and drugmakers are implicated.

Prosecutors alleged Abe used the unheated coagulants while knowing of their potential danger in order to protect importers of the products that had given donations for his research.

Abe's lawyers on Wednesday denied this claim and denounced prosecutors for bowing to "public sentiment" in their demand for prison time.

The court will rule on the case on March 28.