CurrentNeighborhood Health Plan of Rhode IslandPolicy N/A

Vowst (microbiota-based live therapeutic) for prevention of recurrent Clostridioides difficile infection (rCDI)

Defines coverage criteria, exclusions, limitations, quantity limits, and renewal rules for Vowst for prevention of recurrent CDI in members age 18 and older under Medicaid pharmacy scope.

Policy Summary

PayerNeighborhood Health Plan of Rhode Island

PolicyVowst (microbiota-based live therapeutic) for prevention of recurrent Clostridioides difficile infection (rCDI)

Policy CodePolicy N/A

Change TypeClarified (no material change)

Effective DateDec 1, 2023

Next Review Date

Key ActionAuthorization of 30 days for a one-time treatment may be granted when all approval criteria are met; prescriber must be or consult with an infectious disease specialist or gastroenterologist and documentation supporting recurrent CDI and prior antibiotic therapy must be provided.

SourceLink

POLICY UPDATE CHANGES

Reviewed dates listed: 9/23, 5/24, 6/25; package insert reference March 2025 cited.

1Covered Indication (prevention of rCDI)

0Renewable authorizations allowed

12Quantity limit per 30 days

Coverage Summary

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

coverage_stance: covered_with_criteria. scope_summary: Defines coverage criteria, exclusions, limitations, quantity limits, and renewal rules for Vowst for prevention of recurrent CDI in members age 18 years and older under Medicaid pharmacy scope. subject: Vowst (microbiota-based live therapeutic) for prevention of recurrent Clostridioides difficile infection (rCDI). policy effective date: 2023-12-01; last_review: 2025-06. Short indication: Vowst is indicated to prevent the recurrence of Clostridioides difficile infection (CDI) in individuals 18 years of age and older following antibacterial treatment for recurrent CDI (rCDI) (package insert). Guideline and package insert sources: Vowst [package insert], Seres Therapeutics Inc; March 2025; and IDSA/SHEA and ACG clinical guidelines for CDI prevention and management.

Authorization Criteria

Initial authorization — Prevention of recurrence of CDI

Authorization of 30 days for a one-time treatment may be granted for prevention of CDI when ALL of the following criteria are met:

ALL of the following

Member is 18 years of age and older
Medication is prescribed by or in consultation with an infectious disease specialist or gastroenterologist
Documentation of recurrent CDI (one of the following):
- Stool test confirming the presence of C. difficile toxin or toxigenic C. difficile
- Member has at least one recurrence after a primary episode and has completed at least 1 round of standard of care oral antibiotic therapy (e.g., metronidazole, fidaxomicin)
- Member has had at least 2 episodes of severe CDI resulting in hospitalization within the past 12 months
Documentation of current/recent CDI episode (ALL of the following):
- Current episode of CDI is controlled: <3 unformed/loose stools per day for 2 consecutive days
  Clinical documentation should state stool frequency and consistency
- Treatment initiation with Vowst will occur 2–4 days after the last dose of at least 10 consecutive days of antibiotics for CDI treatment
  Record dates of last antibiotic dose and planned Vowst administration

Renewal criteria

Coverage cannot be renewed — authorization is one-time only.

ALL of the following

Initial authorization must meet all initial authorization criteria above
No renewals or continuation therapy will be authorized; Vowst is limited to a single 30-day authorization for one treatment course

Limitations / Not covered

ALL of the following

Vowst is not indicated for the treatment of active CDI; requests for treatment (rather than prevention of recurrence) are not covered
All other indications not listed in this policy are considered experimental/investigational and not medically necessary
Coverage will not be provided for members requesting Vowst for the treatment of CDI
Quantity limit: Vowst has a quantity limit of 12 capsules per 30 days (dose = 4 capsules orally once daily for 3 consecutive days)
Administration prerequisites: Complete antibacterial treatment for CDI 2–4 days before initiating Vowst; document completion date of antibacterial therapy

Provider Actions / Billing Rules

Prior Authorization

Prior authorization required (one-time, 30 days)

Authorization of a one-time, 30-day treatment may be granted when all approval criteria are met. The medication must be prescribed by or in consultation with an infectious disease specialist or a gastroenterologist. Documentation supporting recurrent CDI and prior antibiotic therapy must be provided at the time of prior authorization.

Documentation Required

Documentation of recurrent CDI and prior therapies

Providers must document either stool testing confirming C. difficile toxin or toxigenic C. difficile OR a history of at least two severe CDI episodes resulting in hospitalization within the past 12 months. In addition, provide evidence of prior standard-of-care oral antibiotic therapy for CDI and timing of initiation (Vowst should be started 2–4 days after completion of at least 10 consecutive days of antibiotics).

Billing Rule

Quantity limit

Quantity limit: 12 capsules per 30 days. Dosing: 4 capsules once daily for 3 consecutive days.

Denial Risk

Claims denied for non-prevention indications

Claims will be denied for uses that are not prevention of recurrent CDI, including treatment of active CDI, other off-label/non-covered indications, and for any requests to renew coverage (coverage is one-time only).

Background & Evidence

Background: Vowst is indicated to prevent recurrence of CDI in adults (>= 18 years) following antibacterial treatment for rCDI; it is not indicated for treatment of active CDI and other uses are considered experimental/investigational.

This policy references the Vowst package insert (March 2025) and clinical guidelines from IDSA/SHEA and ACG for CDI prevention and management.

Evidence references:

- Vowst [package insert], Seres Therapeutics Inc; March 2025.

- IDSA/SHEA clinical practice guideline: 2021 focused guideline on management of CDI in adults.

- ACG clinical guidelines: Prevention, diagnosis, and treatment of Clostridioides difficile infections.

Definitions

rCDI (definition)Recurrent Clostridioides difficile infection (recurrence after initial episode)

Revision History

2023-12-01effective_date

No explicit statement of material policy change; clinical criteria remain as presented.

2023-09reviewed

No explicit statement of material policy change; clinical criteria remain as presented.

2024-05reviewed

No explicit statement of material policy change; clinical criteria remain as presented.

2025-06reviewed

No explicit statement of material policy change; clinical criteria remain as presented.

2025-03reference_update

Package insert referenced: Vowst [package insert], Seres Therapeutics Inc; March 2025. No explicit statement of material policy change; clinical criteria remain as presented.

Policy Summary

PayerNeighborhood Health Plan of Rhode Island

PolicyVowst (microbiota-based live therapeutic) for prevention of recurrent Clostridioides difficile infection (rCDI)

Policy CodePolicy N/A

Change TypeClarified (no material change)

Effective DateDec 1, 2023

Next Review Date

SourceLink

On This Page

OpenPayer

Vowst (microbiota-based live therapeutic) for prevention of recurrent Clostridioides difficile infection (rCDI)

Coverage Summary

Authorization Criteria

Limitations / Not Covered

Provider Actions / Billing Rules

Coding

Background & Evidence

Revision History