A team of researchers led by Dr Cesar Giron-Hernandez examined the efficacy and safety of paliperidone palmitate (PP) 6-month (PP6M) vs PP3-month (PP3M) long-acting injectable (LAI) in schizophrenia patients from European sites previously stabilized on PP3M or PP1-month (PP1M).
The study is published in Neuropsychiatric Disease and Treatment.
They concluded that PP6M efficacy was non-inferior to PP3M in preventing relapse in the European subgroup previously treated with PP1M or PP3M (consistent with the global study). They did not report any new safety signals in the study.

PP6M (at 700 mg eq. or 1000 mg eq.) or PP3M (at 350 mg eq. or 525 mg eq.) were administered via dorsogluteal injections. The time-to-relapse during the DB (double-blind phase) was the primary outcome measured in the study. Some other evaluations performed were Treatment-emergent adverse events (TEAEs), physical examinations, and laboratory investigations.
Here is a summary of the study results:
Three hundred eighty-four patients entered the DB phase (European sites).
PP6M had 260 patients with a mean age of 40 years, and PP3M had 124 patients with a mean age of 38.8 years.
During the DB phase, 18 patients in PP6M versus 3 in PP3M had a relapse with a percentage relapse-free difference of − 4.9%.
Secondary efficacy endpoints indicated comparable improvements.
There were similarities in TEAE incidence between PP6M (58.8%) and PP3M (54.8%) groups.
The most common TEAEs were Nasopharyngitis, headache, weight gain and pain at the site of injection.
We found that the Efficacy of PP6M is non-inferior to PP3M in preventing relapse in schizophrenia patients who were previously stabilized on doses of PP1M or PP3M, they said.
They also mentioned that PP6M provides flexibility in dosing regimens for increased adherence, where reducing the frequency of injections is desirable. This flexibility optimizes therapeutic management in such patients from European regions.
Further reading:
Giron‐Hernandez C. Efficacy and Safety of Paliperidone Palmitate 6-Month versus Paliperidone Palmitate 3-Month Long-Acting Injectable in European Patients with Schizophrenia: A Post Hoc Analysis of a Global Phase-3 Double-Blind Randomized Non-Inferiority Study. Neuropsychiatr Dis Treat. 2023;19:895-906. https://doi.org/10.2147/NDT.S400342