Aemcolo® (rifamycin)

Aemcolo® (rifamycin)

RedHill announced in October 2019 that it had entered into an exclusive license agreement with Cosmo Pharmaceuticals N.V. for the U.S. rights to Aemcolo® (rifamycin).

Aemcolo® (rifamycin) is an orally administered, delayed release, minimally absorbed antibiotic approved for the treatment of travelers’ diarrhea caused by non-invasive strains of Escherichia coli in adults. Aemcolo® is the first antibiotic engineered with Cosmo Pharmaceuticals’ Multi Matrix Technology (MMX®). MMX technology allows the delivery of active pharmaceutical ingredients in a delayed and controlled manner to the full length of the colon.

Indication and Important Safety Information:

Aemcolo® (rifamycin) is indicated for the treatment of Travelers’ Diarrhea caused by non-invasive strains of Escherichia coli in adults. Aemcolo® is not indicated in patients with diarrhea complicated by fever or bloody stool or due to pathogens other than non-invasive strains of Escherichia coli.  To reduce the development of drug-resistant bacteria and maintain the effectiveness of Aemcolo and other antibacterial drugs,  Aemcolo should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. 


Aemcolo is contraindicated in patients with a known hypersensitivity to rifamycin, any of the other rifamycin class antimicrobial agents (e.g., rifaximin), or any of the components in Aemcolo. 

Warnings and Precautions

  • Risk of Persistent or Worsening Diarrhea Complicated by Fever and/or Bloody Stool: Aemcolo was not shown to be effective in patients with diarrhea complicated by fever and/or bloody stool or diarrhea due to pathogens other than noninvasive strains of coli and is not recommended for use in such patients.  Discontinue use if diarrhea gets worse or persists more than 48 hours and consider alternative antibacterial therapy.
  • Clostridium difficile-associated diarrhea: Evaluate if diarrhea occurs after therapy or does not improve or worsens during therapy.

Adverse Events

Discontinuation of Aemcolo® in clinical trials due to adverse reactions occurred in 1% of patients. The most frequent adverse reactions leading to discontinuation were abdominal pain (0.5%) and pyrexia (0.3%). The most common adverse reactions that occurred in ~2% of Aemcolo®-treated patients in the clinical trials were constipation 3.5% and headache 3.3%. See Full prescribing information for Aemcolo® is available at


To submit adverse event reports or product complaint reports, contact Aries Pharmaceuticals, Inc. at 1(888) 274-3708. You are encouraged to report negative side effects of prescription drugs to the FDA. Visit or call 1-800-FDA-1088 (1-800-332-1088).