Xifaxan denials in California external review

What the reviewers wrote

Where the denial was overturned

Nature of Statutory Criteria/Case Summary: An enrollee has requested authorization and coverage for the medication Xifaxan.There has been a significant amount of investigation into the use of rifaximin in IBS-D over the last decade. Medical literatures performed a meta-analysis to evaluate the risk of adverse effects, specifically the number needed to harm (NNH), amongst common pharmacologic agents used to manage IBS-D. They found that the NNH for rifaximin was 8971 versus 18.3 for tricyclic antidepressant (TCA), concluding that rifaximin has a better safety profile. Further, they found that an adverse event resulting in discontinuation of TCA occurred for every 2.3 patients who benefited from the drug, versus every 846 patients who took rifaximin, further favoring rifaximin versus TCA.

Nature of Statutory Criteria/ Case Summary: The enrollee is requesting reimbursement for four continuous weeks of Xifaxan. The enrollee has irritable bowel syndrome. He completed a lactulose breath test, which tested positive for hydrogen, resulting in a diagnosis of small intestinal bacterial overgrowth (SIBO). Xifaxan was prescribed for four weeks on the basis that hydrogen is best treated with this medication. The physician notes metronidazole is effective only in treating methane. Cipro and tetracycline have not proven to be effective in treating hydrogen. The patient indicates his condition has improved since starting Xifaxan and continues to improve over time. Literature supports the treatment of small intestinal bacterial overgrowth (SIBO) for patients with irritable bowel syndrome with diarrhea (IBS-D) who are positive for hydrogen on the lactulose breath test.

Where the denial was upheld

Physician 1: This patient is a 54-year-old female who has irritable bowel syndrome, constipation predominant subtype (IBS-C) and apparently was tested for small bowel bacteria with positive results. Her treating physician is now recommending treatment with a recently described antimicrobial regimen of Xifaxan and neomycin in an effort to resolve her bacterial overgrowth and symptoms of IBS-C. The Health Plan has denied coverage for Xifaxan on the basis it is considered investigational for treatment of the patient’s medical condition.The issue of the prevalence and putative association of small intestinal bacterial overgrowth with IBS and functional dyspepsia have been and remain controversial.

Nature of Statutory Criteria/Case Summary: An enrollee has requested authorization and coverage for Xifaxan tablet 550 mg three times a day, indefinitely. The records provided for review document that this patient has a history of constipation. The patient’s provider has recommended ongoing treatment with Xifaxan. Xifaxan has been demonstrated to be safe and effective for the treatment of patients with irritable bowel syndrome-diarrhea predominant (IBS-D). Additionally, Xifaxan has been found to be effective for the treatment of patients with small intestinal bacterial overgrowth (SIBO). However, there is concern for the development of resistance to Xifaxan with long-term use. In this case, there is a lack of submitted documentation of IBS-D or SIBO to support an indication for treatment with Xifaxan.

These outcomes describe eligible cases completed through California DMHC’s Independent Medical Review program. They do not estimate the chance that an internal appeal, an external review in another jurisdiction, or your individual case will succeed. Use the record to identify evidence patterns involving Xifaxan, then check the rights and deadlines that apply to your plan.