CurrentViva HealthPolicy IC-0059

Subcutaneous Immune Globulin (SCIG) therapy

Defines prior authorization, dosing, indications, and renewal criteria for SCIG products (e.g., Hizentra, HyQvia, Gamunex-C, Cuvitru, Xembify) for Viva Health members in North Carolina.

Policy Summary

PayerViva Health

PolicySubcutaneous Immune Globulin (SCIG) therapy

Policy CodePolicy IC-0059

Change TypeNo material changes

Effective Date

Next Review DateAug 5, 2025

Key ActionObtain prior authorization with documentation of prior IVIG/SCIG doses and recent BUN/creatinine; initial approvals are for 6 months and renewals every 12 months.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

6 monthsinitial PA

12 monthsrenewal PA

1840/1680/336/1600example max units (28d)

30 days / 6 monthsrenal labs timing

1.37xXembify multiplier

1.30x

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Coverage Criteria — Indications, Dosing, and Switching Rules

Primary Immunodeficiency (Initial Approval)

Covered when ALL of the following are met for Primary Immunodeficiency (PID):

PID general requirements: Baseline values for BUN and serum creatinine obtained within 30 days of request; patient is at least 2 years of age; AND either IgG <200 mg/dL OR both (history of multiple hard-to-treat infections as defined [e.g., ≥4 otitis media in 1 year; ≥2 serious sinus infections in 1 year; ≥2 pneumonias in 1 year; recurrent deep skin/organ abscesses; persistent thrush; need for IV antibiotics; two or more deep-seated infections including septicemia] ) AND deficient antibody response to vaccination with titers drawn before challenge and again 4–8 weeks after vaccination.

Infections criteria are listed in source chunk 4.

Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)

Covered when ALL of the following are met for CIDP (Hizentra and HyQvia only):

CIDP initial maintenance: Patient is at least 18 years of age; physician has assessed baseline disease severity using an objective measure/tool (e.g., INCAT, MRC, 6‑MWT, Rankin); AND SCIG is used as initial maintenance therapy after treatment and stabilization with IVIG OR for re‑initiation of maintenance after relapse requiring IVIG reinduction.

CIDP eligibility limited to Hizentra and HyQvia as noted in source.

Acquired Immune Deficiency (CLL/SLL)

Covered when ALL of the following are met for Acquired Immune Deficiency secondary to CLL/SLL:

IgG threshold options: Patient has IgG <200 mg/dL; OR patient has IgG <500 mg/dL AND recurrent sinopulmonary infections requiring IV antibiotics or hospitalization; OR patient has IgG <500 mg/dL AND both history of multiple hard-to-treat infections (see PID list for examples) AND deficient antibody response to vaccination with titers drawn before challenge and between 4–8 weeks after vaccination.

Other secondary immunodeficiencies evaluated case-by-case.

Dosing and administration criteria

Dosing instructions and criteria when initiating or switching to listed SCIG products:

HyQvia initial ramp-up: When initiating HyQvia, follow the 4‑infusion ramp‑up schedule: infusion 1 (week 1) = total dose (g) × 0.33 (or ×0.25 depending on interval selection); infusion 2 (week 2) = total dose (g) × 0.67 (or ×0.50); infusion 3 (week 4) = total dose (g) ×0.75 (or total dose); infusion 4 (week 7) = total dose (g).

Exact fractional options and intervals appear in source chunk 18.

Xembify switching from IVIG: Start Xembify one week after the last IVIG infusion. Calculate weekly dose = 1.37 × (previous monthly or every‑3‑week IVIG dose in grams / number of weeks between IVIG doses). Xembify may be administered from daily up to every two weeks; a biweekly dose = weekly dose × 2. For frequent dosing (2–7 times/week) divide the weekly dose by the desired number of weekly administrations.

From source chunk 19.

Cuvitru switching from IVIG or HyQvia: Initiate Cuvitru one week after the last IVIG or HyQvia dose. Calculate weekly dose = 1.30 × (previous IVIG or HyQvia dose in grams / number of weeks between doses). May be administered daily up to every two weeks; biweekly dose = 2 × weekly dose; frequent dosing (2–7 times/week) = divide weekly dose by number of administrations per week.

Dosing and conversion rules

Dosing conversion and scheduling rules (applicable when calculating Xembify dosing from prior IVIG or SCIG regimens):

Weekly dose from prior IVIG: Weekly dose = 1.30 × (previous IVIG dose in grams / number of weeks between IVIG doses).

May be administered from daily up to every two weeks (biweekly).

Biweekly dosing: Biweekly dose = calculated weekly dose × 2.

Frequent dosing: For frequent dosing (2–7 times per week): divide the calculated weekly dose by the desired number of administrations per week.2-7 times/week

Applies when converting weekly SCIG regimens to multiple weekly administrations.

Switching from SCIG to Xembify:

Switching from prior SCIG to Xembify

When switching an insured member from a prior SCIG product to Xembify:

Dose equivalence requirement: The weekly dose (in grams) of Xembify should be the same as the weekly dose of the prior SCIG product when switching.weekly dose in grams = prior SCIG weekly dose

This requirement is repeatedly emphasized in the source text.

Dose equivalence when switching SCIG

Covered when maintaining equivalent dosing on product switch

Switching from prior SCIG to Xembify: When switching from a prior SCIG product to Xembify, the weekly dose (in grams) should be the same as the weekly dose of the prior SCIG.weekly dose parity

Repeated statement across multiple fragments in the source.

Switching from prior SCIG to Xembify

Dosing rule when switching to Xembify

Dose equivalence requirement: When switching from prior SCIG to Xembify, the weekly dose (in grams) should be the same as the weekly dose of the prior SCIG.weekly dose = prior SCIG weekly dose

Statement is repeated across multiple source chunks.

Initial dosing when switching to Xembify

Covered when the following dosing condition is met:

Dose equivalence when switching: When switching from any SCIG product to Xembify, the weekly dose (in grams) should be the same as the weekly dose of the prior SCIG.weekly dose = prior SCIG weekly dose

Statement appears repeatedly in the document fragments.

Switching from SCIG — Dosing equivalence

Covered when switching from SCIG if the following dosing equivalence is followed:

Dose equivalence requirement: Weekly dose (in grams) for Xembify should be the same as the weekly dose of the prior SCIG treatment.weekly grams parity

Repeated multiple times in the source; no additional clinical criteria provided in these fragments.

Dosing conversion for frequent SCIG administration

Dosing conversion/administration guidance

Frequent dosing conversion: For frequent dosing (2–7 times per week): divide the prior weekly dose by the desired number of times per week to determine the per‑administration dose.2-7 times/week

Applies when converting weekly SCIG regimens to multiple weekly administrations.

Coverage for Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) is limited to Hizentra and HyQvia only. These products are the only subcutaneous immunoglobulin formulations specified for CIDP maintenance in this policy and must meet the CIDP-specific criteria (age ≥18, documented baseline disease severity, and prior stabilization with IVIG or re-induction with IVIG for relapse) to be covered.

The provided excerpts include dosing conversion formulas and administration frequency guidance but do not list explicit clinical exclusions. Key dosing notes include conversion from prior IVIG to Xembify (e.g., start Xembify one week after the last IVIG and calculate weekly dose using the specified multiplier) and permitted administration intervals ranging from daily up to biweekly.

This document fragment does not contain explicit clinical exclusions. The text in the fragment focuses on dosing tables and repeated switching/dosing instructions rather than listing exclusionary conditions.

No explicit exclusions are stated in the provided excerpt; the content is predominantly dosing and switching guidance for SCIG products.

The chunks referenced here contain repeated statements about dosing equivalence when switching SCIG products and do not specify any coverage exclusions.

These fragments present dosing/switching table content and repeated dosing statements; no explicit coverage exclusions are provided in these sections.

No explicit exclusions are stated in these chunks. The material here relates to billing code and product availability information rather than clinical exclusion criteria.

This policy is intended for non‑Medicare coverage determinations. Where applicable, Medicare National Coverage Determinations (NCDs), Local Coverage Determinations (LCDs), or Local Coverage Articles (LCAs) and associated contractor rules must be followed and may impose different coverage or billing requirements.

For CIDP patients on Hizentra who worsen despite dose escalation, the policy advises that if symptoms worsen on the maximum Hizentra dose of 0.4 g/kg/week, providers should consider reinitiating IVIG and discontinuing Hizentra rather than further increasing SCIG dosing.

Coding — HCPCS, NDC, and Diagnosis Codes

Provider Actions — Prior Authorization, Documentation, and Billing

Prior Authorization

Prior Authorization Validity and Maximum Units

Prior authorization required. Initial PA validity: 6 months; renewals may be approved every 12 months thereafter. Maximum billable units vary by product and indication — follow product-specific max units (examples: Hizentra up to 1840 units/28 days for CIDP and 1680 units/28 days for other indications; Gamunex-C/Gammaked/Gammagard liquid/ERC 336 units/28 days; Cuvitru/Cutaquig 1600 units/28 days; Xembify maintenance 1680 units/21 days; HyQvia maintenance and loading schedules are product- and indication-specific).

Initial PA validity: 6 months; renew every 12 months.
Refer to product-specific Max Units/HCPCS unit limits in policy (see HCPCS Unit section).
HyQvia has separate loading and maintenance billable-unit schedules by indication.

Documentation Required

Document Prior Dose and Use Conversion Formulas

Document prior dosing and source of prior therapy when requesting authorization and when switching products. When converting from IVIG or HyQvia to a subcutaneous product use the specified conversion formulas to calculate the recommended weekly dose (examples: Xembify weekly dose = 1.37 * [previous monthly IVIG dose in grams / number of weeks between IVIG doses]; Cuvitru weekly dose = 1.30 * [previous IVIG or HyQvia dose (g) / number of weeks between doses]). For HyQvia ramp-up, document each ramp-up infusion and the calculated gram fraction per infusion (policy lists the HyQvia 4-infusion ramp-up schedule and the fraction of total grams to administer at each infusion). When switching from another SCIG, document the prior SCIG weekly dose in grams — the weekly grams for the new SCIG should match the prior SCIG weekly grams unless a conversion formula is explicitly required.

Background and Scope

Subcutaneous immune globulin (SCIG) products in this policy include Hizentra, Gammagard Liquid (including ERC), Gamunex‑C, Gammaked, HyQvia, Cuvitru, Cutaquig, and Xembify. SCIG therapy is indicated for primary immunodeficiencies and certain secondary immunodeficiencies, and select products (Hizentra and HyQvia) are specifically noted for maintenance therapy in Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) following IVIG stabilization.

The extracted sections do not establish any step therapy sequence (drug trials required in a specific order) for SCIG agents. The policy specifies product-specific dosing and conversion guidance rather than step‑therapy requirements.

Definitions and Dosing Principles

Primary Immunodeficiency (PID)

DefinitionPrimary Immunodeficiency (PID): group of congenital disorders characterized by impaired antibody production (examples include X‑linked agammaglobulinemia and common variable immunodeficiency)

Typical diagnostic criteriaOften includes IgG <200 mg/dL OR recurrent/hard‑to‑treat infections plus deficient vaccine response with titers drawn before and 4–8 weeks after vaccination

Age thresholdPolicy specifies patient is at least 2 years of age for PID indications

Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)

DefinitionChronic Inflammatory Demyelinating Polyneuropathy (CIDP): an immune‑mediated demyelinating neuropathy treated with IVIG for induction/stabilization

Maintenance with SCIG

References, Appendices, and Revision Notes

A bibliography of references is included in the source document (approximately 37 entries). Package inserts for Xembify, Cutaquig, Hizentra, HyQvia, and other SCIG products, along with clinical guidelines and relevant studies, are cited to support dosing and clinical recommendations.

Appendix 1 lists covered ICD‑10 diagnosis codes applicable to all SCIG products. The appendix enumerates more than 50 specific codes including primary immunodeficiencies, selected lymphoid malignancy codes, and related diagnostic codes that may support coverage.

Appendix 2 provides Medicare information including referenced Local Coverage Articles and the Medicare Administrative Contractor (MAC) jurisdictions and contractors. This appendix lists MAC jurisdiction assignments and contractor contacts relevant to Medicare Part B claims and coverage.

Policy Summary

PayerViva Health

PolicySubcutaneous Immune Globulin (SCIG) therapy

Policy CodePolicy IC-0059

Change TypeNo material changes

Effective Date

Next Review DateAug 5, 2025

Key ActionObtain prior authorization with documentation of prior IVIG/SCIG doses and recent BUN/creatinine; initial approvals are for 6 months and renewals every 12 months.

SourceLink

On This Page

From source chunks 21 and 30.

Switching SCIG to SCIG: When switching from one SCIG product to another, the weekly dose (in grams) should generally be the same as the prior SCIG weekly dose (in grams). Administration may range from daily to biweekly; biweekly dose = prior weekly dose × 2; frequent dosing (2–7 times/week) = prior weekly dose divided by desired number of weekly administrations.

Stated across multiple source chunks (21, 30).

When switching from SCIG, the weekly dose (in grams) for Xembify should be the same as the weekly dose of the prior SCIG treatment (in grams).

Administration may range from daily to biweekly.

When switching from IVIG/HyQvia: include prior dose in grams and interval (weeks) to calculate weekly SCIG dose using plan formulas.
When switching from SCIG: include prior SCIG weekly dose (grams); weekly dose for new SCIG should equal prior weekly grams.
HyQvia ramp-up: document each infusion and use fractions of the total grams per the 4-infusion schedule.

Billing Rule

Use Specified HCPCS / NDC and Billable Units

Product-specific HCPCS codes, NDCs, and billable unit conventions must be used on prior authorization requests and claims. The policy provides HCPCS/NDC mappings and the billable unit definition per product (for example, Hizentra and Xembify billed as 100 mg units using J-codes such as J1559 and J1558 respectively; Cutaquig reported with J1551). Use the HCPCS/NDC listed for the exact presentation being supplied and apply the product-specific billable unit when calculating units to request and bill.

Use the HCPCS code and NDC listed for the exact product presentation on PA and claims.
1 billable unit conventions vary by product (e.g., Hizentra and Xembify: 1 unit = 100 mg; some products list 1 billable unit = 500 mg).
Follow product-specific billable unit math when converting grams to HCPCS units.

Documentation Required

Renal Function Labs Required

Baseline renal function is required for initial requests and renewal monitoring. Obtain BUN and serum creatinine within 30 days of the initial PA request. For renewal, BUN and serum creatinine must have been obtained within the last 6 months and infusion rate/concentration adjusted accordingly if indicated.

Baseline BUN and serum creatinine within 30 days for initial authorization.
Renewal requires BUN and serum creatinine within the prior 6 months and documentation that infusion parameters were reviewed/adjusted if needed.

Documentation Required

Immunologic Testing, Infection History, and CIDP Baseline Assessment

Clinical and immunologic testing may be required to support certain indications. For primary and secondary immunodeficiency indications, document IgG levels and antibody response to vaccination (pre-challenge titers and repeat titers 4–8 weeks post-challenge) and infection history as described in the PID and secondary immunodeficiency criteria. For CIDP, document baseline disease severity using an objective measure (e.g., INCAT, MRC, 6‑MWT, Rankin) and prior stabilization with IVIG when applicable.

PID/secondary immunodeficiency: report IgG level and vaccine challenge titers (pre- and 4–8 weeks post).
Document infection history meeting the policy's frequency/severity thresholds when applicable.
CIDP: include an objective baseline severity assessment and documentation of prior IVIG stabilization for maintenance use.

Note

Operational Notes — No Explicit Denial Rules or Step Therapy; Medicare Precedence

Operational notes and limitations observed in this excerpt: the section does not list any explicit denial triggers, nor does it define a discrete set of authorization/denial decision rules beyond the clinical criteria and documentation items described. No step-therapy requirements are specified in this extract. Medicare Part B NCDs/LCDs/LCAs may supersede or further clarify coverage and billing rules for Part B claims — consult CMS guidance where applicable.

No explicit denial triggers or binary authorization algorithm included in this excerpt — decisions reference meeting clinical and documentation criteria.
No step therapy rules present in the provided section.
For Medicare Part B patients, check applicable NCD/LCD/LCA documents; CMS policy may take precedence for Part B billing/coverage.

Hizentra and HyQvia may be used for maintenance therapy after treatment and stabilization with IVIG (or for re‑initiation after relapse requiring IVIG)

Age threshold and assessmentPatient must be ≥18 years and physician must assess baseline disease severity with an objective measure/tool (e.g., INCAT, MRC, 6‑MWT)

Weekly dose conversion

MethodConvert prior IVIG/HyQvia dose (g) divided by number of weeks between doses, then multiply by product‑specific factor (e.g., Xembify 1.37; Cuvitru 1.30)

Apply intervalInitiate SCIG approximately 1 week after last IVIG or HyQvia dose when using conversion formulas

Frequency adjustmentsAfter conversion, adjust for biweekly or frequent dosing: biweekly = weekly × 2; frequent (2–7×/week) = weekly ÷ administrations/week

Biweekly dose

Biweekly dose ruleBiweekly dose = 2 × weekly dose (use calculated weekly dose and multiply by 2 for biweekly administration)

Applies toStated explicitly for Xembify and Cuvitru in dosing tables and conversion rules

Administration intervalBiweekly is within allowed administration range of daily to every two weeks

HyQvia ramp-up schedule

Ramp‑up scheduleHyQvia initial ramp‑up over 4 infusions at weeks 1, 2, 4, and 7 with escalating fractions of the total dose (e.g., infusion 1 = Dose×0.33 or 0.25; infusion 2 = Dose×0.67 or 0.50; infusion 3 = Dose×0.75 or total dose; infusion 4 = total dose)

PurposeProvides gradual escalation to full maintenance dose per product guidance

Interval optionsRamp‑up described for 3‑week and 4‑week treatment intervals per product directions

Weekly dose (from prior IVIG)

Weekly dose formula referenceWeekly dose (from prior IVIG) = 1.30 × (previous IVIG dose (g) ÷ number of weeks between IVIG doses) — provided as a product conversion example

UseUsed when calculating Cuvitru weekly dosing from prior IVIG per source; similar forms exist for other products with different multipliers

Adjust for administrationAfter weekly calculation, determine per‑administration amounts for biweekly or frequent schedules

When switching from SCIG, weekly dose should equal prior SCIG weekly grams

PrincipleWhen switching from one SCIG product to another, the weekly dose (in grams) for the new product should equal the weekly dose (in grams) of the prior SCIG

DocumentationPrior SCIG weekly dose in grams should be documented in authorization requests to support equivalent dosing

AdministrationMay be administered daily up to every two weeks; adjust per‑administration amount accordingly

Frequent dosing conversion instruction

DefinitionFrequent dosing = 2–7 times per week; divide the weekly dose by the number of administrations per week to determine per‑administration dose

Calculation guidanceUse prior weekly dose (g) ÷ desired administrations/week to set each dose when scheduling multiple weekly administrations

ApplicabilityApplies when converting weekly SCIG regimens to daily or near‑daily dosing schedules

Weekly dose

Weekly dose conceptWeekly dose refers to the total grams of immunoglobulin administered in one week and is used as the basis for conversions and schedule adjustments

Role in conversionWeekly dose is calculated from prior IVIG/HyQvia dosing using product multipliers and is preserved when switching SCIG products

Use in billingWeekly grams are used to derive billable units per product according to product unit conventions

SCIG abbreviation

AbbreviationSCIG = subcutaneous immunoglobulin

ContextSCIG products include Hizentra, Cuvitru, Cutaquig, Xembify, and others referenced in the policy

UseTerm used throughout policy to denote subcutaneous route formulations and related dosing rules

Frequent dosing conversion instruction

InstructionWhen dosing SCIG 2–7 times/week, divide the prior weekly dose (grams) by the desired number of administrations per week to determine the per‑administration dose

ExampleIf weekly dose = 10 g and dosing 5×/week, per‑administration dose = 10 g ÷ 5 = 2 g per administration

Applies toUsed for conversions from IVIG/HyQvia or when switching between SCIG products and choosing frequent dosing schedules

Covered diagnosis codes (definition)

PurposeAppendix 1 lists the ICD‑10 diagnosis codes accepted for immunoglobulin coverage under this policy

ScopeIncludes primary immunodeficiencies, certain lymphoid malignancies, and other specified immunodeficiency syndromes

ReferenceSee Appendix 1 in the policy document for the full enumerated list of covered ICD‑10 codes

Product-specific covered codes

Product‑specific codesAdditional ICD‑10 codes applicable only to Hizentra and HyQvia: G61.81, G61.89, G62.89 (CIDP and related polyneuropathies)

ApplicabilityThese codes are limited to Hizentra and HyQvia for CIDP/other specified polyneuropathies per policy appendix

Use in authorizationInclude the appropriate ICD‑10 code on prior authorization and claims to indicate product eligibility