OSAKA (Kyodo) -- The Osaka High Court on Thursday upheld a lower court ruling that sentenced a former doctor to two years and six months in prison for the assisted death of a woman with amyotrophic lateral sclerosis, a rare neurological disease also known as Lou Gehrig's disease, in western Japan in 2019.

Naoki Yamamoto, 47, was found guilty by the Kyoto District Court of conspiring with a fellow doctor to administer a lethal dose of a sedative to Yuri Hayashi, 51, in her Kyoto apartment on Nov. 30, 2019, at her request. ALS is a progressive neurological condition for which there is currently no cure or treatment.

The other doctor, Yoshikazu Okubo, 46, is currently appealing his 18-year prison sentence on the same charge.

Euthanasia is not legally recognized in Japan.

In upholding the lower court ruling, Presiding Judge Yuko Tsuboi recognized Yamamoto played a subordinate role, while noting he shared a "tacit understanding" with Okubo regarding the crime.

Tsuboi also criticized Yamamoto for "showing an extreme disregard for human life," given that he accepted 1.3 million yen ($9,000) from Hayashi as a fee and carried out the crime shortly after their first meeting.

During the appeal, Yamamoto's defense continued to argue for an acquittal, claiming it was factually incorrect that he conspired with Okubo.

Yamamoto was previously convicted of murdering his 77-year-old father in 2011 by unspecified means, for which he has been sentenced to 13 years in prison.