ModifiedHealth NetPolicy CP PMN.224

Tenapanor (Ibsrela, Xphozah) Coverage Criteria

Policy governing medical necessity and prior authorization criteria for tenapanor products Ibsrela (for IBS-C) and Xphozah (for hyperphosphatemia in dialysis-dependent CKD) for Health Net lines of business noted in the document.

Policy Summary

PayerHealth Net

PolicyTenapanor (Ibsrela, Xphozah) Coverage Criteria

Policy CodePolicy CP PMN.224

Change TypeAdded Xphozahdosing and plan redirections

Effective Date

Next Review Date

Key ActionSubmit prior authorization with documentation showing diagnosis, prior therapy trials/failures, prescriber specialty, and dosing within limits.

SourceLink

POLICY UPDATE CHANGES

Xphozah (tenapanor) was added to the policy as an indicated product for reducing serum phosphorus in adults with CKD on dialysis as add-on therapy.

Added Xphozah (tenapanor) to the policy.

Clarified that criteria do NOT apply to California Exchange Plans and requests for those plans should be reviewed using HIM.PA.174.

Removed Xphozah 10 mg strength due to product discontinuation.

For IBS-C, added redirection to Linzess and Trulance and aligned Medicaid (HIM) line of business; removed Commercial and added HIM line of business.

Step therapy requirements do not apply for Illinois HIM requests effective 1/1/2026 per IL HB 5395.

2FDA-approved indications

100 mg/dayIbsrela max dose

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Coverage Criteria

Initial Therapy - Ibsrela

Covered when ALL of the following are met:

Ibsrela initial: Request is for Ibsrela; diagnosis of Irritable Bowel Syndrome with Constipation (IBS-C); age >= 18 years; failure of one bulk-forming laxative (e.g., psyllium [Metamucil], methylcellulose [Citrucel], calcium polycarbophil [FiberCon]) unless clinically significant adverse effects are experienced or all are contraindicated; failure of generic lubiprostone unless contraindicated or clinically significant adverse effects are experienced; failure of linaclotide unless contraindicated or clinically significant adverse effects are experienced; failure of plecanatide (Trulance) unless contraindicated or clinically significant adverse effects are experienced; dose does not exceed 100 mg (2 tablets) per day.

Approval duration: 12 months

Initial Therapy - Xphozah

Covered when ALL of the following are met:

Xphozah initial: Request is for Xphozah; diagnosis of hyperphosphatemia associated with chronic kidney disease (CKD); member is on dialysis; age >= 18 years; prescribed by or in consultation with a nephrologist; member meets one of the following: (a) failure after a 4-week trial of calcium acetate at up to maximally indicated doses (e.g., serum phosphorus >= 5.5 mg/dL) unless contraindicated or clinically significant adverse effects are experienced; (b) hypercalcemia as evidenced by recent (within prior 30 days) corrected total serum calcium > 10.2 mg/dL; (c) history of severe vascular and/or soft-tissue calcifications; (d) plasma parathyroid hormone (PTH) >= 150 pg/mL on two consecutive measurements within the past 180 days; or failure of a 4-week trial of a non-calcium phosphate binder (e.g., lanthanum carbonate, sevelamer carbonate) at up to maximally indicated doses unless contraindicated or clinically significant adverse effects are experienced; Xphozah is prescribed as add-on therapy to phosphate binder therapy; dose does not exceed 60 mg per day (2 tablets per day).

Approval duration: 12 months

Continuation Therapy - Ibsrela

Covered when ALL of the following are met:

Ibsrela continued: Request is for Ibsrela; member meets one of the following: currently receiving medication via Centene benefit, or member has previously met initial approval criteria (including documented prior therapy failures when applicable); member is responding positively to therapy; if request is for a dose increase, new dose does not exceed 100 mg (2 tablets) per day.

Approval duration: 12 months

Continuation Therapy - Xphozah

Covered when ALL of the following are met:

Xphozah continued: Request is for Xphozah; member meets one of the following: currently receiving medication via Centene benefit, or member has previously met initial approval criteria (including prior documentation of indication); member is responding positively to therapy (e.g., reduction in serum phosphorus from pretreatment level or maintenance of serum phosphorus < 5.5 mg/dL); Xphozah remains prescribed as add-on therapy to phosphate binder therapy; if request is for a dose increase, new dose does not exceed 60 mg per day (2 tablets per day).

Approval duration: 12 months

Non‑FDA approved (off‑label) indications for tenapanor products are not authorized under this policy unless there is sufficient documentation of efficacy and safety consistent with the Health Plan's off‑label use policies (see HIM.PA.154 for health insurance marketplace and CP.PMN.53 for Medicaid) and any applicable evidence of coverage documents. Requests for non‑FDA indications should include supporting clinical documentation (for example, office notes, lab results, or other relevant information) that demonstrates the member meets the off‑label authorization criteria.

These criteria do NOT apply to California Exchange Plans. Requests for members enrolled in California Exchange Plans must be reviewed using policy HIM.PA.174 rather than this policy.

If a request is for a non‑FDA approved indication and the off‑label criteria are not met, coverage is not authorized under this policy. Providers may submit additional clinical evidence or rationale referencing the Health Plan's off‑label policies (HIM.PA.154 or CP.PMN.53 as applicable) and should include pertinent documentation (eg, office chart notes, labs, imaging, or peer‑reviewed literature) to support any consideration outside the FDA‑approved indications.

Coding, Availability & Dosing

Key dosing and treatment targets

Serum phosphorus treatment goalMaintenance target: serum phosphorus < 5.5 mg/dL

Ibsrela maximum daily doseMaximum dose: 100 mg/day

Xphozah maximum daily doseMaximum dose: 60 mg/day

Provider Actions & Authorization Requirements

Prior Authorization

Prior Authorization Required

Prior authorization is required for Ibsrela and Xphozah. Requests must include sufficient clinical documentation demonstrating that the member meets all applicable approval criteria before coverage will be considered.

Applies to initial and continuation requests.
Approval duration (when approved): 12 months.

Prior Authorization

Prior Authorization and Plan-Specific Redirection

Plan- and line-of-business specific rules may redirect or exclude review under this policy. Requests for California Exchange plans should be reviewed using HIM.PA.174. As of the March 2025 updates, the policy applies to the HIM line of business (Medicaid) and includes redirection for IBS‑C requests to preferred agents (Linzess and Trulance) consistent with HIM strategy. For Illinois (HIM) requests, certain step therapy requirements do not apply as of 1/1/2026 per IL HB 5395.

California Exchange plans: use HIM.PA.174 (requests may be redirected).
HIM line of business: redirects IBS‑C requests to Linzess and Trulance per updated HIM strategy.

Background

Tenapanor is a small‑molecule inhibitor of the intestinal sodium/hydrogen exchanger NHE3. It is indicated in adults as two distinct products: Ibsrela for the treatment of irritable bowel syndrome with constipation (IBS‑C), and Xphozah as an adjunctive therapy to phosphate binders to reduce serum phosphorus in adults with chronic kidney disease on dialysis when binder therapy alone is inadequate or not tolerated. Prescribing information and this policy include product‑specific requirements for prescriber specialty, prior therapy trials, and maximum daily dosing (Ibsrela ≤ 100 mg/day; Xphozah ≤ 60 mg/day).

Definitions

inv-21: IBS-C definition

Definition (term)IBS-C = irritable bowel syndrome with constipation

Clinical contextUsed as the indication for Ibsrela per policy approval criteria (adult patients, diagnosis required)

Related policy actionsStep therapy and prior-therapy requirements specified for IBS-C in initial approval criteria

inv-22: NHE3 definition

Definition (term)NHE3 = sodium/hydrogen exchanger 3

Mechanism relevanceTenapanor is an NHE3 inhibitor (mechanism cited in clinical background)

Appendix reference

Denial Risk

Documentation and Denial Risk

Requests lacking adequate documentation to support the indication and that required step-therapy or redirection criteria have been met may be denied. Ensure submitted records clearly document prior therapies, contraindications, intolerances, and clinical response.

Incomplete or missing office notes, medication trials, lab results, or specialty consultation notes increases denial risk.
Requests for non‑FDA indications require sufficient documentation per off‑label policies HIMPA.154 (Marketplace) or CP.PMN.53 (Medicaid).

Documentation Required

Provider Responsibility and Required Documentation

Provider is responsible for following applicable Health Plan administrative policies and for submitting contemporaneous clinical documentation supporting medical necessity. Documentation should demonstrate how the member meets each approval criterion.

Acceptable documentation includes: office chart notes, medication history, pharmacy records, lab results, specialist consultation notes, and prior authorization forms.
Providers remain responsible for the medical decision and must comply with state and Health Plan continuity/administrative rules.

Step Therapy

Step Therapy and Redirection to Preferred Agents

For IBS‑C requests, the plan may redirect to preferred agents. Prior to Ibsrela approval, step therapy requires failure or contraindication/intolerance to specified agents (e.g., trial of a bulk‑forming laxative such as psyllium, failure of generic lubiprostone, and failure of Linzess and Trulance) unless otherwise exempt. For HIM (Medicaid) members, redirection to Linzess and Trulance is applied per HIM policy updates.

Step therapy sequence (unless contraindicated/intolerant): bulk‑forming laxative (e.g., psyllium), generic lubiprostone, Linzess, Trulance.
Dose limit for Ibsrela: does not exceed 100 mg (2 tablets) per day.
Illinois HIM: step therapy exceptions effective 1/1/2026 per IL HB 5395; HIM line‑of‑business redirections to preferred agents are applied.

inv-23: Tenapanor (Xphozah)

Product name and active ingredientTenapanor (marketed as Xphozah for hyperphosphatemia and Ibsrela for IBS-C)

Prescribing referencePrescribing information cited: Xphozah Prescribing Information (Ardelyx) October 2023; Ibsrela PI April 2022

Indications in policyXphozah indicated to reduce serum phosphorus in adults with CKD on dialysis as add-on therapy to phosphate binders when criteria met

Dosing details in PIXphozah dosing: 30 mg PO twice daily (total 60 mg/day); maximum daily dose 60 mg/day