One of the placebo-controlled trials1 was extended to assess the long-term efficacy of lurasidone (40–160 mg/day) compared to quetiapine (200–800 mg/day) in 292 people.6 Flexible dosing was allowed. At 12 months, the estimated probability of relapse was 23.7% in people receiving lurasidone compared with 33.6% in those receiving quetiapine. Discontinuation rates were high (48% for lurasidone, 61% for quetiapine).6
Another longer term comparative study enrolled patients with stable schizophrenia. After 12 months, 20% of people (82/410) receiving lurasidone had relapsed compared with 16% (32/198) receiving risperidone.7
The most common adverse events in the short-term trials were somnolence (17% of patients), extrapyramidal symptoms (14%), akathisia (13%), insomnia (10%) and nausea (10%). Tachycardia, blurred vision, abdominal pain, diarrhoea, decreased appetite, rash, pruritus, hypertension and elevated creatine kinase also occurred in 1–10% of people. Prolactin elevations were more frequent with lurasidone than with placebo (2.8% vs 1%). QT prolongation did not seem to be a problem in the trials.
In the six-week trials, weight gain was modest with lurasidone compared with placebo (mean change of 0.43 kg vs –0.02 kg). In the longer term comparative studies, people taking lurasidone were less likely to have gained weight than those taking quetiapine6 and risperidone.7
As with other antipsychotics, lurasidone can cause neuroleptic malignant syndrome, tardive dyskinesia and orthostatic hypotension. It should be used with care in patients at risk of hypotension or seizures. Lurasidone should not be used in elderly patients with dementia-related psychosis because of an increased risk of death with antipsychotics.
Lurasidone should be started at 40 mg once daily, taken with food. In the trials no additional benefit was seen with the 120 mg dose. The recommended starting dose in moderate to severe renal impairment is 20 mg. Lurasidone should not be used in people with severe hepatic impairment and the recommended starting dose is 20 mg in those with moderate impairment.
Peak concentrations are reached 1–3 hours after taking an oral dose and steady-state concentrations are reached within seven days. The drug’s elimination half-life is 18 hours and most of the dose is excreted in the faeces.
Concomitant use of strong cytochrome P450 (CYP) 3A4 inhibitors (ketoconazole, clarithromycin, ritonavir) and inducers (rifampicin, St John’s wort, phenytoin) is contraindicated as lurasidone is metabolised by CYP3A4. The lurasidone dose should be halved in people taking moderate inhibitors (diltiazem). Patients should avoid grapefruit juice as it may increase lurasidone exposure.
Lurasidone is a category B1 drug in pregnancy. In animal studies, no fetal toxicities were observed. However, exposure during the third trimester in pregnant women increased the risk of extrapyramidal and withdrawal symptoms in newborns. Some babies had to be managed in the intensive care unit. Breastfeeding is not recommended with lurasidone as it has been found to be excreted in the milk of lactating rats.
In general, lurasidone was better than placebo in patients with acute schizophrenia. However, efficacy was not consistent at all doses and a dose–response relationship could not be shown. It is unclear how lurasidone will compare to other drugs in the class.