CurrentCareSourcePolicy N/A

Gamastan (immune globulin (human)) coverage

Defines prior-authorization coverage criteria for Gamastan (immune globulin (human)) for prophylaxis of hepatitis A, measles, varicella, and rubella for CareSource members in Arkansas PASSE.

Policy Summary

PayerCareSource

PolicyGamastan (immune globulin (human)) coverage

Policy CodePolicy N/A

Change TypeNew policy

Effective DateMar 1, 2024

Next Review DateN/A

Key ActionObtain prior authorization demonstrating indication criteria and specialist involvement before administering Gamastan.

SourceLink

POLICY UPDATE CHANGES

New policy for Gamastan created

4covered indications listed (Hepatitis A, Measles, Varicella, Rubella)

Prior_Authorization Requiredbenefit type/status

J1460; J1560billing codes listed

2024-03-01policy effective date

Coverage Criteria for Gamastan

Hepatitis A (Initial and Reauthorization rules)

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Covered when ALL of the following are met for Hepatitis A (initial authorization):

Hepatitis A initial: 1) Medication is prescribed by or in consultation with an infectious disease specialist; AND 2) Member has been exposed to hepatitis A within the past 2 weeks OR is traveling to an area with endemic hepatitis A and Gamastan will be administered prior to departure; AND 3) Member does not have clinical manifestations of hepatitis A.Administer within two weeks of exposure; travel dosing: 0.1 mL/kg IM for up to 1 month; 0.2 mL/kg IM for up to 2 months.

If all requirements are met, one dose will be approved for 7 days. For travel >2 months, see reauthorization rules.

Hepatitis A reauthorization

Reauthorization for Hepatitis A:

Hepatitis A reauth: If Gamastan was previously approved for travel to an area with endemic hepatitis A and member length of stay will be longer than 2 months, medication may be reauthorized.Repeat dosing 0.2 mL/kg IM every 2 months; up to 12 months total.

Reauthorization allowed only under travel length criteria; medication will be approved for member length of stay up to 12 months if criteria met.

Measles (Initial)

Covered when ALL of the following are met for Measles (initial authorization):

Measles initial: 1) Member has not been vaccinated against measles; AND 2) Medication is prescribed by or in consultation with an infectious disease specialist; AND 3) Member has not had measles previously; AND 4) Member was exposed to measles within the last 6 days; AND 5) Member is either an immunocompromised child OR pregnant and lacks evidence of immunity and will not receive measles vaccine.Administer within 6 days of exposure; immunocompromised child dosing: 0.5 mL/kg IM (max 15 mL).

Gamastan is not administered at the same time as measles vaccine. If criteria met, one dose approved for 7 days; medication will not be reauthorized.

Varicella (Initial)

Covered when ALL of the following are met for Varicella (initial authorization):

Varicella initial: 1) Member is immunocompromised; AND 2) Medication is prescribed by or in consultation with an infectious disease specialist; AND 3) Member was exposed to varicella within the last 72 hours; AND 4) Member is unable to access Varicella Zoster Immune Globulin (Human).Administer within 72 hours of exposure; dosing 0.6 mL/kg to 1.2 mL/kg IM.

If all requirements are met, one dose will be approved for 7 days. Medication will not be reauthorized.

Rubella (Initial)

Covered when ALL of the following are met for Rubella (initial authorization):

Rubella initial: 1) Member is pregnant; AND 2) Medication is prescribed by or in consultation with an infectious disease specialist; AND 3) Member was exposed to rubella within the last 72 hours; AND 4) Member will not consider therapeutic abortion.Administer within 72 hours of exposure; dosing 0.55 mL/kg IM.

If all requirements are met, one dose will be approved for 7 days. Medication will not be reauthorized. Other indications not listed are considered not medically necessary.

Treatment of conditions not specifically listed in this policy is considered not medically necessary. Providers should refer to the plan’s Off-Label policy for requests of Gamastan for any other indications; such requests may be denied.

CareSource considers Gamastan (immune globulin (human)) not medically necessary for indications that are not specifically listed in this policy. Requests for unlisted uses are subject to denial.

Initial Therapy Rules by Indication

Initial therapy

Initial therapy rules by indication:

Initial HepA: See Hepatitis A initial criteria: specialist involvement, exposure/travel timing, absence of clinical disease.Administer within two weeks of exposure; travel dosing by length of stay (0.1 mL/kg IM up to 1 month; 0.2 mL/kg IM up to 2 months).

One dose approved for 7 days for initial authorization.

Initial Measles: See Measles initial criteria: susceptible/unvaccinated, specialist involvement, exposure within 6 days; immunocompromised child dosing 0.5 mL/kg IM (max 15 mL).Administer within 6 days of exposure.

One dose approved for 7 days; not given concurrently with measles vaccine; medication will not be reauthorized.

Initial Varicella: See Varicella initial criteria: immunocompromised, exposure within 72 hours, inability to access VZIG; dosing 0.6-1.2 mL/kg IM.Administer within 72 hours of exposure.

One dose approved for 7 days; medication will not be reauthorized.

Initial Rubella: See Rubella initial criteria: pregnant, exposure within 72 hours, will not consider therapeutic abortion; dosing 0.55 mL/kg IM.Administer within 72 hours of exposure.

One dose approved for 7 days; medication will not be reauthorized.

Continuation and Reauthorization Criteria

Hepatitis A continuation

Hepatitis A continuation/repeat dosing when travel exceeds 2 months:

Hep A continuation: Repeat dosing 0.2 mL/kg IM every 2 months if length of stay >2 months.Repeat dosing interval: every 2 months; maximum program length up to 12 months.

Reauthorization allowed only when previously approved for travel and member length of stay will exceed 2 months; medication will be approved up to 12 months if criteria met.

Billing and Coding

Billing codesHCPCS

J1460	Immune globulin (human), non-specific, intramuscular, up to 1 ml
J1560	Immune globulin (human), 500 mg

Measles post-exposure window

Measles post-exposure windowAdminister within 6 days of exposure; one dose approved for 7 days

Measles immunocompromised child dosing0.5 mL/kg IM (max 15 mL)

ReauthorizationMedication will not be reauthorized for measles

Hepatitis A post-exposure window

Hepatitis A post-exposure windowAdminister within 2 weeks of exposure; one dose approved for 7 days

Travel dosing (≤1 month)0.1 mL/kg IM

Travel dosing (≤2 months) and short-term exposure dosing0.2 mL/kg IM

Reauthorization for travel >2 monthsRepeat dosing 0.2 mL/kg IM every 2 months up to 12 months

Varicella post-exposure window

Varicella post-exposure windowAdminister within 72 hours of exposure; one dose approved for 7 days

Dosing range0.6 mL/kg to 1.2 mL/kg IM

Access requirementMember must be unable to access Varicella Zoster Immune Globulin (Human) to qualify

Rubella post-exposure window

Rubella post-exposure windowAdminister within 72 hours of exposure; one dose approved for 7 days

Dosing0.55 mL/kg IM

Pregnancy criterionMember is pregnant and will not consider therapeutic abortion; specialist involvement required

Provider Actions and Documentation Requirements

Prior Authorization

Prior Authorization Required

Prior authorization is required for Gamastan (immune globulin (human)) when billed under the medical benefit (HCPCS J1460, J1560). Requests must be submitted and approved before administration to avoid potential denial of payment.

Affected codes: J1460, J1560
Benefit type: Medical

Documentation Required

Clinical Prior Authorization Criteria

Prior authorization requests must document that the clinical criteria for the requested indication are met. For all indications, the prescriber must be the ordering provider or have consulted with an infectious disease specialist, and documentation must include exposure timing and the clinical rationale for passive immunization.

Document consultation or prescription by an infectious disease specialist where required
Include date/time of exposure and justification for Gamastan rather than alternative prophylaxis or vaccines
Show vaccination or prior immunity status when relevant (e.g., measles, rubella)

Step Therapy

Varicella Step Requirement

For varicella (post‑exposure modification), members must be immunocompromised, exposed within the last 72 hours, and be unable to access Varicella Zoster Immune Globulin (Human). The request must include evidence that VZIG is unavailable and the prescribed dose (0.6–1.2 mL/kg IM).

Exposure window: within 72 hours
Dose allowed: 0.6 mL/kg to 1.2 mL/kg IM
Must document inability to access Varicella Zoster Immune Globulin (Human)

Documentation Required

Required Clinical Documentation

Prescriptions should be written by or in consultation with an infectious disease specialist for the listed indications (hepatitis A post‑exposure or pre‑travel prophylaxis, measles post‑exposure modification, varicella post‑exposure modification, rubella exposure in pregnancy). Required documentation includes exposure timing, absence of clinical disease when applicable, vaccination and immunity history, pregnancy and abortion considerations for rubella, and the dosage/quantity requested.

Include exposure timing (e.g., within 2 weeks for hepatitis A, within 6 days for measles, within 72 hours for varicella/rubella)
Confirm member does not have clinical disease when required (e.g., no clinical hepatitis A)
For rubella in pregnancy: document that the member will not consider therapeutic abortion

Denial Risk

Unlisted Indications / Reauthorization

Requests for indications not explicitly listed in this policy are considered not medically necessary and may be denied. Gamastan will not be reauthorized for continuation therapy; approval is limited to a single dose when criteria are met.

Unlisted/off‑label indications are not covered per policy
Authorization is for one dose (approved for 7 days when criteria met)

Step Therapy Requirements

Step	Requirement
1	Must document inability to access Varicella Zoster Immune Globulin (Human) (VZIG); member must be immunocompromised, prescribed by or in consultation with an infectious disease specialist, and exposed to varicella within the last 72 hours.

Quantity Limits and Dosing

Gamastan — Quantity limits and reauthorization

Standard initial quantity limitOne dose approved for 7 days for most initial indications

Hepatitis A reauthorization ruleReauthorization allowed only for travel when length of stay >2 months with repeat dosing 0.2 mL/kg IM every 2 months up to 12 months

Measles reauthorizationMedication will not be reauthorized for measles

Varicella reauthorizationMedication will not be reauthorized for varicella

Rubella reauthorizationMedication will not be reauthorized for rubella

Definitions

Gamastan (immune globulin (human)) — Definition

DefinitionGamastan (immune globulin (human)) is a passive immunizing polyclonal human immune globulin used for pre- and post-exposure prophylaxis against hepatitis A, measles, varicella, and rubella

Product characteristicsHuman immune globulin solution for intramuscular injection; derived from human blood

MechanismProvides passive immunity by neutralizing viruses through polyclonal antibodies

Background

Gamastan (immune globulin (human)) is a polyclonal human immune globulin used for passive immunization. It is indicated in this policy for pre‑ and post‑exposure prophylaxis against hepatitis A, measles, varicella, and rubella. The product is derived from human plasma and carries the associated risks of blood‑derived products; providers should follow the dosing and timing guidance in the applicable indication criteria.

Site of Care

Note

Site of care — not specified

Site of care for Gamastan infusion is not specified in the policy (no restriction to infusion center or other specific setting).

Policy lists benefit type as Medical but does not define a required site of care