Jennifer Kern Sliwa

Onset of efficacy with acute long-acting injectable paliperidone palmitate treatment in markedly to severely ill patients with schizophrenia: post hoc analysis of a randomized, double-blind clinical trial

BackgroundThis post hoc analysis (trial registration: ClinicalTrials.gov NCT00590577) assessed onset of efficacy and tolerability of acute treatment with once-monthly paliperidone palmitate (PP), a long-acting atypical antipsychotic initiated by day 1 and day 8 injections, in a markedly to severely ill schizophrenia population.MethodsSubjects entering the 13-week, double-blind trial were randomized to PP (39, 156, or 234 mg [25, 100, and 150 mg eq of paliperidone, respectively]) or placebo. This subgroup analysis included those with a baseline Clinical Global Impressions-Severity (CGI-S) score indicating marked to severe illness. PP subjects received a 234-mg day 1 injection (deltoid), followed by their assigned dose on day 8 and monthly thereafter (deltoid or gluteal). Thus, data for PP groups were pooled for days 4 and 8. Measures included Positive and Negative Syndrome Scale (PANSS), CGI-S, Personal and Social Performance (PSP), and adverse events (AEs). Analysis of covariance (ANCOVA) and last-observation-carried-forward (LOCF) methodologies, without multiplicity adjustments, were used to assess changes in continuous measures. Onset of efficacy was defined as the first time point a treatment group showed significant PANSS improvement (assessed days 4, 8, 22, 36, 64, and 92) versus placebo, which was maintained through end point.ResultsA total of 312 subjects met inclusion criterion for this subgroup analysis. After the day 1 injection, mean PANSS total scores improved significantly with PP (all received 234 mg) versus placebo at day 4 (P = 0.012) and day 8 (P = 0.007). After the day 8 injection, a significant PANSS improvement persisted at all subsequent time points in the 234-mg group versus placebo (P < 0.05). PANSS improvements were greater from day 36 through end point in the 156-mg group (P < 0.05) and only at end point in the 39-mg group (P < 0.05). CGI-S and PSP scores improved significantly in the 234-mg and 156-mg PP groups versus placebo at end point (P < 0.05 for both, respectively); improvement in the 39-mg group was not significant. The most common AEs for PP-treated subjects (≥10%, any treatment group) were headache, insomnia, schizophrenia exacerbation, injection site pain, and agitation.ConclusionsIn this markedly to severely ill population, acute treatment with 234 mg PP improved psychotic symptoms compared with placebo by day 4. After subsequent injections, observed improvements are suggestive of a dose-dependent effect. No unexpected tolerability findings were noted.

Onset of efficacy and tolerability following the initiation dosing of long-acting paliperidone palmitate: post-hoc analyses of a randomized, double-blind clinical trial.

BackgroundPaliperidone palmitate is a long-acting injectable atypical antipsychotic for the acute and maintenance treatment of adults with schizophrenia. The recommended initiation dosing regimen is 234 mg on Day 1 and 156 mg on Day 8 via intramuscular (deltoid) injection; followed by 39 to 234 mg once-monthly thereafter (deltoid or gluteal). These post-hoc analyses addressed two commonly encountered clinical issues regarding the initiation dosing: the time to onset of efficacy and the associated tolerability.MethodsIn a 13-week double-blind trial, 652 subjects with schizophrenia were randomized to paliperidone palmitate 39, 156, or 234 mg (corresponding to 25, 100, or 150 mg equivalents of paliperidone, respectively) or placebo (NCT#00590577). Subjects randomized to paliperidone palmitate received 234 mg on Day 1, followed by their randomized fixed dose on Day 8, and monthly thereafter, with no oral antipsychotic supplementation. The onset of efficacy was defined as the first timepoint where the paliperidone palmitate group showed significant improvement in the Positive and Negative Syndrome Scale (PANSS) score compared to placebo (Analysis of Covariance [ANCOVA] models and Last Observation Carried Forward [LOCF] methodology without adjusting for multiplicity) using data from the Days 4, 8, 22, and 36 assessments. Adverse event (AE) rates and relative risks (RR) with 95% confidence intervals (CI) versus placebo were determined.ResultsPaliperidone palmitate 234 mg on Day 1 was associated with greater improvement than placebo on Least Squares (LS) mean PANSS total score at Day 8 (p = 0.037). After the Day 8 injection of 156 mg, there was continued PANSS improvement at Day 22 (p ≤ 0.007 vs. placebo) and Day 36 (p < 0.001). Taken together with results in the 39 mg and 234 mg Day 8 arms, these findings suggest a trend towards a dose-dependent response. During Days 1 to 7, AEs reported in ≥2% of paliperidone palmitate subjects (234 mg) and a greater proportion of paliperidone palmitate than placebo subjects were: agitation (3.2% vs. 1.3%; RR 2.52 [95% CI 0.583, 10.904]), headache (4.0% vs. 3.8%; RR 1.06 [95% CI 0.433, 2.619]), and injection site pain (6.7% vs. 3.8%; RR 1.79 [95% CI 0.764, 4.208]). Days 8 to 36 AEs meeting the same criteria in the 156 mg Day 8 arm were: anxiety (3.1% vs. 2.5%; RR 1.24 [95% CI 0.340, 4.542]), psychotic disorder (2.5% vs. 1.3%; RR 1.99 [95% CI 0.369, 10.699]), dizziness (2.5% vs. 1.3%; RR 1.99 [95% CI 0.369, 10.699]), and injection site pain (2.5% vs. 1.3%; RR 1.99 [95% CI 0.369, 10.699]). Corresponding Days 8 to 36 AEs in the 39 mg Day 8 group were: agitation (4.5% vs. 4.4%; RR 1.03 [95% CI 0.371, 2.874]), anxiety (3.9% vs. 2.5%; RR 1.55 [95% CI 0.446, 5.381]), and psychotic disorder (2.6% vs. 1.3%; RR 2.07 [95% CI 0.384, 11.110]) while in the 234 mg Day 8 group it was anxiety (3.1% vs. 2.5%, RR 1.25 [95% CI 0.342, 4.570]).ConclusionsSignificantly greater symptom improvement was observed by Day 8 with paliperidone palmitate (234 mg on Day 1) compared to placebo; this effect was maintained after the 156 mg Day 8 injection, with a trend towards a dose-dependent response. No unexpected tolerability findings were noted in the first week or month after the initiation dosing.Trial registrationClinicalTrials.gov: NCT#00590577

Paliperidone palmitate and risperidone long-acting injectable in subjects with schizophrenia recently treated with oral risperidone or other oral antipsychotics.

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Paliperidone palmitate versus oral risperidone and risperidone long-acting injection in patients with recently diagnosed schizophrenia: a tolerability and efficacy comparison.

Early in the course of illness, patients with schizophrenia may be particularly susceptible to adverse events (AEs). In this post-hoc, subgroup analysis of a 13-week, double-blind, double-dummy, multicenter study, patients recently diagnosed with schizophrenia (⩽5 years) were administered once-monthly flexible-dose paliperidone palmitate (PP) (n=161; initiation doses, 150 mg eq day 1 and 100 mg eq day 8) [PP doses can be expressed as milligram equivalents (mg eq) of paliperidone or as milligrams (mg) of PP. 150 mg eq paliperidone=234 mg PP; 100 mg eq paliperidone=156 mg PP. In the USA, dosing tends to be expressed in mg] or oral risperidone [during initiation of risperidone long-acting injection (RLAI) days 1–28] and biweekly flexible-dose RLAI (n=173; initial injection day 8). Assessments were performed at baseline and days 4, 15, 22, 36, 64, and 92. Because of RLAI’s release profile, data through day 22 correspond to oral risperidone in the RLAI arm. During this period, the AE profile and onset of efficacy of PP and oral risperidone were similar. The overall AE rates at week 13 for PP and RLAI were 54.7 and 50.3%, respectively, for any AE; 11.2 and 8.1% for extrapyramidal symptom–related AEs; and 2.5 and 2.3% for prolactin-related AEs. No significant differences in the mean weight change, most metabolic parameters, or mean efficacy measures were observed at end point. In patients with recently diagnosed schizophrenia, the tolerability and efficacy of PP and RLAI were generally similar over 13 weeks.

Tolerability of initiation doses of once-monthly paliperidone palmitate in patients with recently diagnosed schizophrenia in an acute treatment trial.

Objective: To examine the tolerability of the recommended initiation doses for once-monthly injectable paliperidone palmitate in patients who have recently been diagnosed with schizophrenia and for whom high doses may pose tolerability concerns. Methods: A post hoc analysis from a 13-week double-blind study of patients with schizophrenia randomized 1:1:1:1 to placebo or paliperidone palmitate at 25, 100, or 150 mg equivalents (mg eq) of paliperidone (corresponding to 39, 156, or 234 mg respectively). This analysis focused on the recently diagnosed subgroup (≤5 years; N = 146) who received the recommended initiation dosage of paliperidone palmitate [150 mg eq on day 1 (n = 109) followed by 100 mg eq on day 8 (n = 39)] or placebo (n = 37). Adverse events (AEs), reported in ≥2% of patients receiving paliperidone palmitate during days 1–7 or ≥5% during days 8–36, and in a higher percentage of patients receiving paliperidone palmitate than placebo, were identified. AE relative risks (RRs) and 95% confidence intervals (CIs) were determined. A RR was considered potentially significant when its 95% CI did not include 1. Results: Overall, day 1–7 AE rates were 37.6% (41 of 109) and 29.7% (11 of 37) with paliperidone palmitate and placebo respectively; injection site pain (5.5% versus 2.7%, RR 2.0; 95% CI 0.25 to 16.37), agitation (4.6% versus 2.7%; RR 1.7; 95% CI 0.21 to 14.06), and headache (3.7% versus 0.0%; RR 3.1; 95% CI 0.17 to 56.41) met the ≥2% criteria. Day 8–36 AE rates were 41.0% (16 of 39) and 37.8% (14 of 37) with paliperidone palmitate and placebo respectively; anxiety (5.1% versus 0.0%; RR 4.8; 95% CI 0.24 to 95.76) met the ≥5% criteria. Key limitations were that some patients may have been ill for a significant time before formal diagnosis and that the number of patients is low in this subgroup, limiting the ability to detect statistical significance for AE RRs. Conclusions: Paliperidone palmitate initiation doses (150 mg eq day 1, 100 mg eq day 8) were tolerated in this subgroup of patients who were recently diagnosed with schizophrenia, with no unexpected findings. Although the same size was small, these data identified AEs that may be encountered during the week and month after initiation dosing. These findings may assist clinicians when paliperidone palmitate is considered an appropriate treatment choice for these patients.

Are the long-acting intramuscular formulations of risperidone or paliperidone palmitate associated with post-injection delirium/sedation syndrome? An assessment of safety databases.

Long-acting injectable (LAI) formulations of antipsychotics are valuable treatment alternatives for patients with psychotic disorders, and understanding their safe use is critical. Post-injection delirium/sedation syndrome (PDSS) has been reported following treatment with one atypical antipsychotic LAI. Clinical databases of risperidone LAI and paliperidone palmitate were explored to identify if cases of PDSS had been observed. No cases of PDSS were identified in 15 completed trials of 3,164 subjects (approximately 115,000 injections) or the postmarketing safety database of risperidone LAI. Only one case of PDSS was identified among 10 completed trials (3,817 subjects, 33,906 injections) of paliperidone palmitate—that case having been reported in a patient randomized to treatment with placebo. Examination of these prospective databases finds no evidence that risperidone LAI and paliperidone palmitate are associated with PDSS and suggest that findings seen with another antipsychotic LAI are not generalizable.

Effects of acute paliperidone palmitate treatment in subjects with schizophrenia recently treated with oral risperidone

OBJECTIVE To examine efficacy and safety of acute treatment with paliperidone palmitate in subjects with schizophrenia whose disease remained symptomatic despite recent treatment with oral risperidone. METHODS Post hoc analysis of a 13-week, double-blind, placebo-controlled study of subjects with symptomatic schizophrenia randomized to paliperidone palmitate 39, 156, or 234 mg (25, 100, or 150 mg equivalents of paliperidone) or placebo. Paliperidone palmitate subjects received a 234-mg day 1 dose, followed by their assigned dose on day 8 and monthly thereafter. Subjects treated with oral risperidone within 2 weeks before randomization regardless of duration were included. ASSESSMENTS PANSS, CGI-S, PSP scores; AEs. ANCOVA models with LOCF methodology evaluated treatment group differences. RESULTS 216 subjects received prior oral risperidone (paliperidone palmitate 39 mg, n=53; 156 mg, n=58; 234 mg, n=48; placebo, n=57). Median prior risperidone use was 22 days. Significant improvement was observed with paliperidone palmitate 156-mg or 234-mg versus placebo in least-squares mean (SE) score change at end point in PANSS total (156 mg, -15.8 [3.0], p=0.0001; 234 mg, -17.6 [3.2], p=0.0001), CGI-S (156 mg, -0.9 [0.2], p=0.0068; 234 mg, -1.1 [0.2], p=0.0003), and PSP (156 mg, 10.7 [2.3], p=0.0061; 234 mg, 12.9 [2.4], p=0.0009). Most common AEs (≥10%) in any paliperidone palmitate group were insomnia, anxiety, and headache. CONCLUSIONS In subjects with schizophrenia who recently received oral risperidone but who remained symptomatic, acute treatment with monthly doses of 156-mg and 234-mg paliperidone palmitate significantly improved clinical symptoms, global illness ratings, and functioning compared with placebo, with no unexpected safety findings.

Management of antipsychotic treatment discontinuation and interruptions using model-based simulations.

Background Medication nonadherence is a well described and prevalent clinical occurrence in schizophrenia. These pharmacokinetic model-based simulations analyze predicted antipsychotic plasma concentrations in nonadherence and treatment interruption scenarios and with treatment reinitiation. Methods Starting from steady state, pharmacokinetic model-based simulations of active moiety plasma concentrations of oral, immediate-release risperidone 3 mg/day, risperidone long-acting injection 37.5 mg/14 days, oral paliperidone extended-release 6 mg/day, and paliperidone palmitate 117 mg (75 mg equivalents)/28 days were assessed under three treatment discontinuation/interruption scenarios, ie, complete discontinuation, one week of interruption, and four weeks of interruption. In the treatment interruption scenarios, pharmacokinetic simulations were performed using medication-specific reinitiation strategies. Results Following complete treatment discontinuation, plasma concentrations persisted longest with paliperidone palmitate, followed by risperidone long-acting injection, while oral formulations exhibited the most rapid decrease. One week of oral paliperidone or risperidone interruption resulted in near complete elimination from the systemic circulation within that timeframe, reflecting the rapid elimination rate of the active moiety. After 1 and 4 weeks of interruption, minimum plasma concentrations were higher with paliperidone palmitate than risperidone long-acting injection over the simulated period. Four weeks of treatment interruption followed by reinitiation resulted in plasma levels returning to predicted therapeutic levels within 1 week. Conclusion Due to the long half-life of paliperidone palmitate (25–49 days), putative therapeutic plasma concentrations persisted longest in simulated cases of complete discontinuation or treatment interruption. These simulations may help clinicians better conceptualize the impact of antipsychotic nonadherence on plasma concentrations, and the impact of medication-specific reinitiation strategies after intermittent nonadherence.

Paliperidone palmitate versus risperidone long-acting injection in markedly-to-severely ill schizophrenia subjects: onset of efficacy with recommended initiation regimens.

OBJECTIVE To examine onset of efficacy of two long-acting injectable atypical antipsychotics in markedly-to-severely ill schizophrenia subjects. METHODS This subgroup analysis included 292 subjects with baseline Clinical Global Impressions-Severity scores of markedly ill or worse from a 13-week, randomized, double-dummy noninferiority study (NCT00589914). Subjects received either: 1) paliperidone palmitate (PP; 234 mg day 1 and 156 mg day 8 [corresponding to 150 and 100 milligram equivalents of paliperidone, respectively], both administered in deltoid muscle, followed by once-monthly flexible dosing in deltoid or gluteal muscle) and risperidone long-acting injection (RLAI)-matched placebo injections; or, 2) RLAI (25 mg, days 8 and 22; followed by biweekly flexible dosing) and PP-matched placebo injections. RLAI subjects received oral risperidone days 1-28; PP subjects received oral placebo. Because of RLAIs release profile, data through day 22 correspond to oral risperidone. Assessments included Positive and Negative Syndrome Scale (PANSS) and adverse event (AE) reports. Paired t-tests assessed within-group changes. RESULTS LS mean (SE) PANSS total scores improved significantly (both p<.001) with PP and oral risperidone by day 4 (-5.0 [0.6] and -3.4 [0.6], respectively) through day 22; and with PP and RLAI through end point (-21.5 [1.9] and -18.6 [1.9], respectively). The between-group difference was significant only at day 4 (p=.006). Proportion of subjects with a .30% reduction in PANSS total score was not significantly different between the two groups at day 4 and was significantly greater with paliperidone palmitate than oral risperidone at days 15 and 22 (26.1% versus 12.7%, p=.013; 41.6% versus 32.0%, p=.048, respectively). Most common AEs (.5% in either treatment group): headache (PP 6.3% and RLAI 14.0%), insomnia (10.6% and 10.7%), somnolence (7.8% and 1.3%), akathisia (7.0% and 5.3%), schizophrenia (8.5% and 5.3%), agitation (5.6% and 2.0%), and injection site pain (5.6% and 1.3%). CONCLUSIONS Using the recommended dosing regimens for PP and RLAI, both PP and oral risperidone (used during RLAI initiation) improved symptoms of schizophrenia in markedly-to-severely ill subjects at days 4-22.

Onset and persistence of efficacy by symptom domain with long-acting injectable paliperidone palmitate in patients with schizophrenia

Introduction: Several long-acting injectable (LAI) second-generation antipsychotics are now available for the management of schizophrenia. As patients with schizophrenia frequently present with diverse and challenging symptoms, it is important to understand the effects of antipsychotics in treating these different symptom subgroups and the timing of these responses. Areas covered: For this review, data from two randomized, double-blind trials were analyzed in respect to the onset and persistence of effects on several measures of psychopathology (as measured by the Positive and Negative Syndrome Scale [PANSS]) after treatment with LAI paliperidone palmitate (PP) (NCT00590577 and NCT00589914). Expert opinion: Symptom reductions from baseline with PP were significant by day 4 for all five PANSS factors in both studies. Some effects may have been driven by the presence or absence of a placebo response. A significant effect for PP versus placebo was observed for all major symptom domains for one or more doses of PP during the first month of treatment. Once established, most (but not all) significant responses persisted to the end point. Similar improvements were observed in PANSS scores with PP and oral risperidone. Dose-dependent trends were observed for the effect of PP on positive, negative and uncontrolled hostility/excitement symptoms.