Aetna modified CPB 1050 for ADAMTS13, recombinant-krhn (Adzynma), effective December 4, 2025. Here's what billing teams need to know.
Aetna, a CVS Health company, updated Clinical Policy Bulletin 1050 to define coverage criteria for Adzynma — a recombinant enzyme replacement therapy for congenital thrombotic thrombocytopenic purpura (cTTP). The policy activates HCPCS code J7171 and CPT code 85397 for covered claims and adds strict genetic confirmation and activity-level thresholds that your team must document before submitting. Miss either criterion, and you're looking at a claim denial.
Quick-Reference Table
| Field | Detail |
|---|---|
| Payer | Aetna, a CVS Health company |
| Policy | ADAMTS13, Recombinant-krhn (Adzynma) — CPB 1050 |
| Policy Code | CPB 1050 |
| Change Type | Modified |
| Effective Date | December 4, 2025 |
| Impact Level | High |
| Specialties Affected | Hematology, Infusion Therapy, Specialty Pharmacy |
| Key Action | Verify genetic testing documentation (biallelic ADAMTS13 mutations) and ADAMTS13 activity level below 10% before submitting J7171 claims |
Aetna Adzynma Coverage Criteria and Medical Necessity Requirements 2025
The Aetna Adzynma coverage policy under CPB 1050 covers one indication: congenital thrombotic thrombocytopenic purpura (cTTP). That's it. There is no off-label use coverage here.
To establish medical necessity for initial approval, two criteria must both be met — no exceptions. First, the member must have a confirmed cTTP diagnosis through genetic testing showing biallelic mutations in the ADAMTS13 gene. Second, the member's ADAMTS13 activity level must be less than 10% at the time of diagnosis.
Both requirements must be documented before you submit. If you have genetic testing results but no documented activity level, Aetna will not approve the claim. If you have the activity level but the genetic testing shows only one mutation instead of biallelic mutations, you don't meet criteria either. Both boxes must be checked.
Precertification is required for all Aetna participating providers and members in applicable plan designs. Call (866) 752-7021 or fax (888) 267-3277 to start the precertification process. For Statement of Medical Necessity forms, use Aetna's Specialty Pharmacy Precertification portal.
A site of care utilization management policy also applies to Adzynma. Aetna's Site of Care for Specialty Drug Infusions policy governs where this drug can be administered for reimbursement purposes. Before you schedule an infusion, confirm the site of care meets Aetna's requirements — otherwise you're billing the right code in the wrong setting, and that generates denials just as reliably as missing criteria.
Prior authorization requirements here are unambiguous. There is no pathway to coverage without precertification. Don't submit J7171 without it.
Aetna Adzynma Exclusions and Non-Covered Indications
Aetna's position on this is direct: all indications other than cTTP are experimental, investigational, or unproven.
This matters because cTTP and acquired TTP (aTTP) can look similar in the clinical record. Acquired TTP is caused by autoimmune destruction of ADAMTS13, not a genetic deficiency. Adzynma is not covered for aTTP under this policy. If your documentation references TTP without specifying the congenital, genetically confirmed subtype, expect a denial.
There is no indication expansion here, no off-label consideration pathway, and no case-by-case exception process described in CPB 1050. The coverage policy is narrow by design.
Coverage Indications at a Glance
| Indication | Status | Relevant Codes | Notes |
|---|---|---|---|
| Congenital TTP (cTTP) — confirmed biallelic ADAMTS13 gene mutations AND activity level <10% | Covered | J7171, 85397, D69.42 | Precertification required; site of care UM policy applies |
| cTTP — continuation of therapy with documented response | Covered | J7171, 85397, D69.42 | Must show reduction or maintenance of TTP events, increased platelet count (85049), or decreased LDH (83615, 83625) |
| All other indications (including acquired TTP) | Not Covered | — | Considered experimental, investigational, or unproven |
Aetna Adzynma Billing Guidelines and Action Items 2025
This is where Adzynma billing gets operationally complex. The criteria are tight, the precertification process is mandatory, and the documentation requirements span multiple test types. Here's what your team needs to do before submitting claims under CPB 1050.
| # | Action Item |
|---|---|
| 1 | Confirm genetic test documentation is in the chart before you submit. Aetna requires biallelic mutations in the ADAMTS13 gene confirmed by genetic testing. A clinical note saying "suspected cTTP" is not enough. The actual genetic test results showing biallelic mutations must be in the medical record. CPT 85397 covers functional ADAMTS13 activity testing — but you need genetic confirmation separately. |
| 2 | Document the ADAMTS13 activity level at diagnosis. The threshold is less than 10%. This is not a one-time post-treatment level — it must be the level at the time of diagnosis. Make sure the chart ties the specific activity result to the diagnosis date, not a follow-up visit. |
| 3 | Get precertification before administering the drug. Call (866) 752-7021 or fax the SMN form through Aetna's Specialty Pharmacy Precertification portal. Administering Adzynma without prior authorization and then trying to appeal is a painful, low-success process. Get it before the infusion. |
| 4 | Verify site of care before scheduling the infusion. Aetna's Site of Care UM policy applies here. Check whether the planned infusion setting — office, infusion center, hospital outpatient — meets Aetna's approved sites under that policy. If it doesn't, you're creating a billing problem before the patient walks in the door. |
| 5 | Build your reauthorization documentation process now. Continuation of therapy requires evidence that the member is responding. Aetna accepts three response markers: reduction or maintenance in the number of TTP events, increase in platelet count, or decrease in LDH levels. That means CPT codes 85049 (platelet count) and 83615 or 83625 (LDH levels) need to be billed and documented at appropriate intervals — not just at reauthorization time. Build that into your monitoring schedule from day one. |
| 6 | Use ICD-10 code D69.42 consistently. This is the diagnosis code for congenital and hereditary thrombocytopenia purpura. Don't use unspecified TTP codes or codes for acquired disease. Mismatched diagnosis codes on J7171 claims will trigger denials even when the clinical documentation is solid. |
| 7 | Bill J7171 in the correct units. J7171 describes injection, adamts13, recombinant-krhn, 10 IU per unit. Confirm your dosing documentation supports the units billed. Over-billing units without dose documentation is a compliance exposure, not just a denial risk. |
| 8 | Use CPT 96374 for IV push administration if applicable. CPT 96374 covers therapeutic, prophylactic, or diagnostic injection via intravenous push. If the drug is given as an IV push rather than an infusion, make sure your administration code matches the actual method used. |
If you're not sure how the site of care policy interacts with your specific infusion setting, talk to your compliance officer before the effective date. The interaction between CPB 1050 and the Site of Care UM policy adds a layer of complexity that's easy to miss until you're looking at a denial.
| Previous Version | Current Version |
|---|---|
| Coverage is considered experimental and investigational for all indications | Coverage is considered medically necessary when specific criteria are met |
| Prior authorization is not required | Prior authorization is required for initial treatment |
| Documentation must include clinical history | Documentation must include clinical history |
| Re-review every 24 months | Re-review every 12 months with updated clinical documentation |
CPT, HCPCS, and ICD-10 Codes for ADAMTS13 Recombinant-krhn Under CPB 1050
Covered HCPCS Codes (When Selection Criteria Are Met)
| Code | Type | Description |
|---|---|---|
| J7171 | HCPCS | Injection, adamts13, recombinant-krhn, 10 IU |
Covered CPT Codes (When Selection Criteria Are Met)
| Code | Type | Description |
|---|---|---|
| 85397 | CPT | Coagulation and fibrinolysis, functional activity, not otherwise specified (e.g., ADAMTS-13), each analyte |
Key ICD-10-CM Diagnosis Codes
| Code | Description |
|---|---|
| D69.42 | Congenital and hereditary thrombocytopenia purpura |
D69.42 is your primary diagnosis code for cTTP claims under this policy. Use it on every J7171 claim. Any mismatch between the diagnosis code and the drug indication triggers a coverage policy conflict that medical review will flag.
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