What are the guidelines for converting to Invega Trinza (paliperidone palmitate) from other antipsychotic regimens?

Guidelines for Converting to Invega Trinza (Paliperidone Palmitate)

Patients must be adequately stabilized on Invega Sustenna (once-monthly paliperidone palmitate) for at least four months before converting to Invega Trinza (three-month paliperidone palmitate). This is the essential prerequisite for any conversion to the three-month formulation.

Conversion Process from Invega Sustenna to Invega Trinza

1. Prerequisite: Patient must be clinically stable on Invega Sustenna for at least 4 months, with the last two doses being the same strength.

2. Dosing Conversion:

   • Convert to Invega Trinza using the following equivalent dose multiplier:
     • Last Invega Sustenna 78 mg → Invega Trinza 273 mg
     • Last Invega Sustenna 117 mg → Invega Trinza 410 mg
     • Last Invega Sustenna 156 mg → Invega Trinza 546 mg
     • Last Invega Sustenna 234 mg → Invega Trinza 819 mg

3. Timing: Administer Invega Trinza when the next monthly Invega Sustenna dose would have been due.

4. Injection Site: Can be administered in either deltoid or gluteal muscle.

   • For deltoid injection: Use weight-adjusted needle (1-inch 23G for <90kg; 1.5-inch 22G for ≥90kg)
   • For gluteal injection: Use 1.5-inch 22G needle regardless of weight

Converting from Other Antipsychotics to Invega Trinza

Step 1: Convert to Invega Sustenna First

When converting from oral antipsychotics or other LAIs, patients must first be stabilized on Invega Sustenna:

1. From Oral Risperidone:

   • For patients on ≥4 mg/day of oral risperidone, consider bridging with oral medication for ≥7 days after first Invega Sustenna injection 1
   • Bridging has been associated with significant reductions in hospitalization days

2. From Oral Antipsychotics (non-risperidone):

   • Initiate Invega Sustenna the day after discontinuing previous oral antipsychotic 2
   • No oral supplementation required with proper loading dose

3. From Other LAIs:

   • Initiate Invega Sustenna at the time of the next scheduled injection of the previous LAI 2

Step 2: Invega Sustenna Initiation Protocol

1. Day 1: 150 mg equivalent (234 mg) in deltoid muscle
2. Day 8: 100 mg equivalent (156 mg) in deltoid muscle
3. Monthly Maintenance: 25-150 mg equivalent (39-234 mg) with 75 mg equivalent (117 mg) being the recommended dose 2

Step 3: Stabilization Period

• Maintain patient on Invega Sustenna for at least 4 months
• Ensure the last two monthly doses are the same strength
• Monitor for adequate symptom control and tolerability

Step 4: Convert to Invega Trinza

• Follow the dose conversion table above
• Administer when next monthly dose would have been due

Special Considerations

• Missed Doses: If more than 6 weeks have passed since the last Invega Sustenna injection, re-initiation protocol depends on the duration since last injection 2

• Renal Impairment: Dose adjustment required for patients with mild renal impairment (CrCl 50-80 mL/min) 2

• Hepatic Impairment: No dose adjustment needed for mild to moderate hepatic impairment 2

• Elderly Patients: Same dosage as younger adults with normal renal function; adjust if age-related decline in CrCl is present 2

Monitoring After Conversion

• Regular clinical assessment of treatment response
• Monitor for side effects, particularly extrapyramidal symptoms
• Regular monitoring of weight, BMI, blood pressure, glucose, and lipids 3
• Antipsychotic treatment should be continued for at least 12 months after achieving remission 4, 3

Invega Trinza offers the advantage of four-times-a-year dosing 5, which may improve adherence and reduce relapse rates compared to more frequently dosed medications. Studies have shown that conversion to long-acting injectable paliperidone palmitate is associated with reductions in hospitalization days and emergency department visits, even when dosing is suboptimal 1.