<p>Request follows reports that Biogen and the FDA held off-the-books meetings before the drug's approval that may have violated FDA protocol</p>
<p>FDA approved Aduhelm earlier this month, despite advisory committee's conclusion that there was not enough evidence to support its effectiveness</p>
<p>Several experts have said the available evidence about Aduhelm raises significant doubts about its effectiveness</p>
<p>Agency says it has granted approval on the condition that drug maker Biogen conduct a new clinical trial</p>
<p>8-mg dose of naloxone hydrochloride nasal spray now approved with 2-mg and 4-mg doses</p>