Step therapy for Palynziq (pegvaliase-pqpz)
Defines UnitedHealthcare's step therapy requiring trial of sapropterin dihydrochloride (Kuvan) before coverage for Palynziq for members new to therapy; existing Palynziq users documented in claims are allowed continued coverage. Affects providers prescribing enzyme therapy for phenylketonuria.
Revised requirement for trial of sapropterin therapy to exclude patients with two null mutations in trans.
Coverage Criteria for Palynziq (pegvaliase-pqpz)
Initial Therapy
Palynziq will be approved when ALL of the following (one of the alternative criteria) are met:
Member new to therapy must meet one of these alternatives; members currently on Palynziq as documented in claims history are allowed continued coverage.
Members new to Palynziq therapy are excluded from initial coverage unless they meet the policy's step therapy exceptions. Specifically, initial approval requires either a documented history of therapeutic failure, documented contraindication, or documented intolerance to sapropterin dihydrochloride (include the date of the sapropterin trial and the reason for failure/intolerance), OR documentation that the patient has two null mutations in trans that make sapropterin an inappropriate candidate. Members currently on Palynziq as documented in claims history will be allowed continued coverage of their current therapy.
UnitedHealthcare may use automated approval and reauthorization processes that rely on previous claim or medication history, diagnosis codes, and claim logic; these processes can result in approvals issued solely on claims/diagnosis information. Such automated approvals do not replace the clinical coverage criteria: when a member is new to therapy the step therapy requirements and documentation rules (for example, recorded sapropterin trial or genetic evidence of two null mutations in trans) remain the clinical standard for medical necessity determinations.
Key Diagnostic / Lab Thresholds
Definitions and Clinical Terms
Provider Actions, Prior Authorization, and Documentation
Prior Authorization Required
Prior authorization is required for Palynziq (pegvaliase-pqpz). Approval is contingent on documentation that the member has failed, has a contraindication to, or is intolerant of sapropterin dihydrochloride (Kuvan), or meets the two-null-mutations criterion. Authorization will be issued for up to 12 months. State mandates, federal requirements, and the member's benefit plan may affect coverage.
- Approval duration: 12 months
- Drug: Palynziq (pegvaliase-pqpz)
- Required prior therapy: sapropterin dihydrochloride (Kuvan) unless excluded
Step Therapy Requirement
Members new to Palynziq must complete a trial of sapropterin dihydrochloride (Kuvan) prior to coverage unless they meet exclusion criteria (see two null mutations or documented contraindication/intolerance). Members currently on Palynziq as documented in claims history are allowed to continue therapy without meeting the step requirement.
- Step therapy: trial of sapropterin required for new-to-therapy members
- Exception: documented two null mutations in trans; documented contraindication or intolerance to sapropterin
- Continuation: existing Palynziq users in claims history allowed continued coverage
Required Documentation for Initial Approval
For initial approval, submit the date(s) of the sapropterin trial and the reason for therapeutic failure, contraindication, or intolerance. Alternatively, provide genetic testing documentation showing two null mutations in trans if sapropterin is not appropriate.
- Document: date of sapropterin (Kuvan) trial
- Document: reason for failure, contraindication, or intolerance to sapropterin
- Or provide: genetic test results confirming two null mutations in trans
Missing Prior Sapropterin Trial Documentation
Failure to provide documentation of a prior sapropterin trial (date and reason for failure/contraindication/intolerance) may result in denial of Palynziq coverage.
- Missing documentation of prior sapropterin trial may trigger denial
- Ensure genetic test results are submitted if relying on two null mutations in trans
Initial Therapy Requirements
Initial Therapy Requirements
Initial approval requirements for Palynziq:
Must be met for members new to therapy; sapropterin trial requirement is excepted when two null mutations in trans are documented.
Continuation Therapy Requirements
Continuation Therapy
Continuation rules for members already on therapy
Claims history is used to identify existing users.
Step Therapy Operational Details
| Step | Requirement | Exceptions / Documentation | Coverage Label |
|---|---|---|---|
| 1 | Trial of sapropterin dihydrochloride (Kuvan or generic) is required prior to coverage of Palynziq for members new to therapy. | Document date of sapropterin trial and reason for therapeutic failure, contraindication, or intolerance. | Covered with criteria |
| – | Patient is excluded from the sapropterin trial requirement if genetic testing documents two null mutations in trans making sapropterin inappropriate. | Provide documentation of genetic testing showing two null mutations in trans. | Covered with criteria |
| – | Members currently on Palynziq as documented in claims history are allowed continued coverage without meeting the step therapy trial requirement for new therapy. | Claims history supporting current Palynziq use will be used to identify existing users. | Covered |
Site of Care and Operational Notes
Site-of-care: medical necessity, supply limits, notification, and automated approvals may apply
For infusion center or other site-of-care settings, medical necessity rules, supply limits, and/or notification requirements may apply; UnitedHealthcare may also use automated approval and re-approval processes based on prior claims/diagnosis history.
Background
Palynziq (pegvaliase-pqpz) is a phenylalanine‑metabolizing enzyme indicated to reduce blood phenylalanine concentrations in adult patients with phenylketonuria who have uncontrolled blood phenylalanine concentrations > 600 micromol/L on existing management. It is positioned in this policy as the therapy subject to step therapy, with sapropterin dihydrochloride (Kuvan) identified as the lower‑cost alternative that must be tried first for members new to therapy unless a documented exclusion applies.
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