Recommended Dosing

The recommended starting dose of GAMIFANT is 1 mg/kg given as an intravenous infusion over 1 hour twice per week (every three to four days). Doses subsequent to the initial dose may be increased based on clinical and laboratory criteria [see Dosage and Administration (2.4)].

Administer GAMIFANT until hematopoietic stem cell transplantation (HSCT) is performed or unacceptable toxicity. Discontinue GAMIFANT when a patient no longer requires therapy for the treatment of HLH.

Monitoring to Assess Safety

Before Initiating GAMIFANT Treatment

Conduct testing for latent tuberculosis infections using the purified protein derivative (PPD) or IFNγ release assay and evaluate patients for tuberculosis risk factors prior to initiating GAMIFANT. Administer tuberculosis prophylaxis to patients at risk for tuberculosis, or known to have a positive PPD test result, or positive IFNγ release assay.

During GAMIFANT Treatment

Monitor for tuberculosis, adenovirus, EBV and CMV every 2 weeks and as clinically indicated.

Pre-Medications and Concomitant Medication Information

Pre-Medications

Administer prophylaxis for Herpes Zoster, Pneumocystis jirovecii, and for fungal infections prior to GAMIFANT administration.

Concomitant Medications

For patients who are not receiving baseline dexamethasone treatment, begin dexamethasone at a daily dose of at least 5 to 10 mg/m2 the day before GAMIFANT treatment begins. For patients who were receiving baseline dexamethasone, they may continue their regular dose provided the dose is at least 5 mg/m2. Dexamethasone can be tapered according to the judgment of the treating physician [see Clinical Studies (14)].

Dose Modification Based on Response

The GAMIFANT dose may be titrated up if disease response is unsatisfactory (see Table 1) [see Clinical Pharmacology (12.3)]. After the patient’s clinical condition is stabilized, decrease the dose to the previous level to maintain clinical response.

Instructions for Preparation and Administration

Preparation

GAMIFANT vials are for single-use only.

Prepare the solution for infusion as follows:

• Calculate the dose (mg/kg), total volume (mL) of GAMIFANT required and the number of GAMIFANT vials needed based on patient actual body weight [see Dosage and Administration (2.1)].
• Inspect GAMIFANT vials visually for particulate matter and discoloration prior to dilution. GAMIFANT is a clear to slightly opalescent, colorless to slightly yellow liquid. Do not administer if discolored or foreign particulate matter is present.
• Withdraw the necessary amount of GAMIFANT solution and dilute with 0.9% Sodium Chloride Injection, USP to a maximum concentration of 2.5 mg/mL. Do not dilute product to less than 0.25 mg/mL.
• Discard any unused portion left in the vial(s).
• The diluted solution can be placed in either a syringe or an infusion bag, depending on the volume needed.
• Use a gamma irradiated latex-free, polyvinyl chloride (PVC)-free syringe. Do not use with ethylene oxide-sterilized syringes.
• Use a non-PVC polyolefin infusion bag.

Administration

• Administer GAMIFANT diluted solution intravenously over 1 hour through an intravenous line containing a sterile, non-pyrogenic, low-protein binding 0.2 micron in-line filter.
• Do not infuse GAMIFANT concomitantly with other agents and do not add any other product to the infusion bag or syringe.
• Do not store any unused portion of the infusion solution for reuse. Any unused product or waste material should be disposed of in accordance with local requirements.

Storage of Diluted Solution

This product does not contain a preservative.

If not administered immediately:

• Store the diluted solution of GAMIFANT under refrigeration at 2°C to 8°C (36°F to 46°F) for no more than 4 hours from the time of dilution.
• If refrigerated, allow the diluted solution to come to room temperature prior to administration.
• Do not freeze. Do not shake.