The Food and Drug Administration (FDA) has approved Lybalvi (olanzapine and samidorphan) for the treatment of schizophrenia in adults, Alkermes announced. The agency also approved Lybalvi for the treatment of bipolar I disorder in adults, as a monotherapy for maintenance, and as a monotherapy or an adjunct to lithium or valproate for the acute treatment of manic or mixed episodes.
Olanzapine is an antipsychotic, and samidorphan is a new chemical agent and an opioid antagonist. Lybalvi is taken once a day and may be taken with or without food. It will be available in fixed dosage strengths composed of 10 mg of samidorphan and 5 mg, 10 mg, 15 mg, or 20 mg of olanzapine.
The approval is based on data from the ENLIGHTEN clinical development program. In ENLIGHTEN-1, 403 patients who were experiencing an acute exacerbation of schizophrenia took either Lybalvi or placebo for four weeks. At the end of the study, those who had taken Lybalvi had statistically significant reductions from baseline in Positive and Negative Syndrome Scale scores compared with those who took placebo.
ENLIGHTEN-2 evaluated the weight-gain profile of Lybalvi compared with olanzapine over six months in 561 patients with stable schizophrenia. Patients who took Lybalvi had a lower mean percent weight gain at six months compared with those in the olanzapine group and a lower proportion of patients who gained 10%or more of their baseline body weight at six months. The difference in weight gain between the two groups became apparent after the fourth week of the trial, and their rates of weight gain continued to diverge for the remainder of the study. At the sixth week, weight stabilized in the Lybalvi group and remained flat for the rest of the study period.
Lybalvi has a boxed warning about increased mortality in older patients who have dementia-related psychosis. The warning also states that the medication is not approved for the treatment of patients with dementia-related psychosis.
Lybalvi should not be taken by patients who are taking opioids or who are experiencing acute opioid withdrawal. Prior to initiating Lybalvi, there should be at least a seven-day opioid-free interval from the last use of short-acting opioids and at least a 14-day opioid-free interval from the last use of long-acting opioids.
Potential side effects of Lybalvi include dry mouth, sleepiness, dizziness, increased appetite, and constipation.
For related information, see the American Journal of Psychiatry article “How Much of an Advance is the Addition of Samidorphan to Olanzapine?”
