How do you switch from oral medication to a long-acting injectable (LAI)?

Switching from Oral Medication to Long-Acting Injectable (LAI)

When transitioning from oral medication to a long-acting injectable (LAI), establish clinical stability on the oral formulation first, then begin LAI administration while continuing oral medication for the initial overlap period before discontinuing the oral medication. 1

General Principles for Switching to LAI

Step 1: Preparation Phase

• Confirm patient is clinically stable on the oral formulation of the same medication (or equivalent) that will be given as LAI
• Review treatment history and resistance patterns if switching antiretroviral therapy 1
• Screen for contraindications to the specific LAI being considered
• Ensure proper monitoring capabilities are in place for follow-up

Step 2: Initiation Phase

• Begin LAI while continuing oral medication during the overlap period
• The overlap duration depends on the specific medication:
  • For antipsychotics: typically 2-4 weeks of oral and LAI overlap
  • For antiretrovirals (e.g., cabotegravir/rilpivirine): one month oral lead-in before first injection 1

Step 3: Maintenance Phase

• Discontinue oral medication after the appropriate overlap period
• Schedule regular follow-up appointments to monitor efficacy and adverse effects
• Implement increased clinical and laboratory monitoring initially 1

Medication-Specific Considerations

Antipsychotic LAIs

• Ensure patient tolerates the oral version before initiating LAI
• Different LAIs have specific loading dose requirements:
  • Some require loading doses (higher initial doses)
  • Some require continued oral supplementation during initiation
• Patient acceptance is higher than clinicians often assume, even in first-episode psychosis 1

Antiretroviral LAIs (e.g., cabotegravir/rilpivirine)

• Only use in patients without documented or suspected resistance to either agent 1
• Not recommended for patients with chronic HBV infection unless HBV treatment is continued 1
• Requires rescreening for HBV before switching to this tenofovir-sparing regimen 1
• Establish viral suppression on oral therapy before switching 1

Antibiotics (e.g., dalbavancin)

• For bacteremia treatment, ensure at least 7 days of IV therapy before switching to long-acting options 1
• Monitor for treatment-emergent resistance with long-acting antibiotics 1

Clinical Monitoring After Switch

• Increased monitoring frequency immediately after switch:
  • For antiretrovirals: viral load at 1 month and then every 3 months for a year 1
  • For all LAIs: monitor for injection site reactions and medication-specific adverse effects
• Ensure patients understand the importance of keeping scheduled injection appointments

Common Pitfalls and How to Avoid Them

• Underestimating patient acceptance: Many clinicians assume patients will reject injectable options, but evidence shows many patients accept LAIs when properly educated 1
• Inadequate overlap period: Insufficient overlap between oral and injectable formulations can lead to subtherapeutic levels
• Missing follow-up: Establish clear follow-up protocols and reminder systems for patients on LAIs
• Resistance development: For antiretrovirals, carefully review resistance history before switching 1
• Pharmacy dispensing errors: Ensure proper coordination between prescribers and pharmacy for LAI administration 1

LAIs offer advantages of guaranteed adherence, reduced daily pill burden, and potentially improved outcomes. The key to successful transition is proper patient selection, adequate overlap between oral and injectable formulations, and appropriate follow-up monitoring.