Some IV NK1 RA antiemetics are formulated with synthetic surfactants1

Synthetic surfactants have been associated with adverse events1-3

  • Synthetic surfactants are solubilizers used in some IV NK1 RA formulations1
  • Synthetic surfactants are pharmacologically active compounds that have been associated with adverse events including systemic HSRs and ISAEs1-3
Emend® IV
(fosaprepitant) for injection*1,2,4,5
Varubi® IV
(rolapitant) injectable emulsion†‡6-8
Synthetic surfactant Polysorbate 80 Kolliphor® HS 15
Date synthetic surfactant was used in formulation of any drug product 1986 October 2017
Varubi IV was the first drug to utilize Kolliphor HS 15 in the US
Synthetic surfactant real-world experience Known
Associated with HSRs, including anaphylaxis and ISAEs
Not well established
Limited clinical data in humans
* Emend is a trademark of Merck & Co., Inc.
Varubi is a registered trademark of TerSera Therapeutics LLC.
No head-to-head studies of CINVANTI® (aprepitant) injectable emulsion and Varubi IV were performed. This presentation is a factual description of the physical characteristics of the products and is not intended to convey any comparative safety information.
In February 2018, distribution of Varubi IV was suspended by the manufacturer9

Fosaprepitant is formulated with polysorbate (PS) 80—a compound associated with adverse events1-4

PS 80 is a synthetic surfactant used to solubilize injectable chemotherapy and supportive care drugs. As a pharmacologically active compound, it has also been linked to adverse events in oncology patients.1-3

Reactions associated with PS 801-3
PS 80 Systemic Adverse Events
PS 80 Infusion Site Adverse Reactions
  • Due to sequential administration of NK1 RAs and chemotherapy, adverse events may be inadvertently attributed solely to chemotherapy10

Infusion site adverse events occurred with fosaprepitant (via peripheral line) in a study of patients receiving AC-based chemotherapy11

  • The Mayo Clinic Rochester published a chart review in 2014 of 98 patients who received Emend IV (via peripheral line) and 44 patients who received oral Emend prior to AC-based chemotherapy11
  • ISAEs were seen in 35% of patients receiving fosaprepitant vs 2% of patients for oral aprepitant11
  • The Mayo Clinic discontinued use and removed Emend IV from its AC-based CINV prophylaxis protocol due to the rate of ISAEs11
A need existed for a new IV formulation of aprepitant that delivers the same efficacy as fosaprepitant without a synthetic surfactant.

AC=anthracycline/cyclophosphamide; HSR=hypersensitivity reaction; ISAE=infusion site adverse event; PS 80=polysorbate 80.


CINVANTI is a substance P/neurokinin-1 (NK1) receptor antagonist, indicated in adults, in combination with other antiemetic agents, for the prevention of: acute and delayed nausea and vomiting associated with initial and repeat courses of highly emetogenic cancer chemotherapy (HEC) including high-dose cisplatin as a single-dose regimen; delayed nausea and vomiting associated with initial and repeat courses of moderately emetogenic cancer chemotherapy (MEC) as a single-dose regimen; and nausea and vomiting associated with initial and repeat courses of MEC as a 3-day regimen.

Limitations of Use: CINVANTI has not been studied for treatment of established nausea and vomiting.

Important Safety Information


CINVANTI is contraindicated in patients with hypersensitivity to any of the components of CINVANTI.

Concurrent use of pimozide with CINVANTI is contraindicated.

Warnings and Precautions

Clinically Significant CYP3A4 Drug Interactions

Aprepitant is a substrate, weak-to-moderate (dose-dependent) inhibitor, and an inducer of CYP3A4.

  • Use of CINVANTI with other drugs that are CYP3A4 substrates may result in increased plasma concentration of the concomitant drug.
    • Use of pimozide with CINVANTI is contraindicated due to the risk of significantly increased plasma concentrations of pimozide, potentially resulting in prolongation of the QT interval, a known adverse reaction of pimozide.
  • Use of CINVANTI with strong or moderate CYP3A4 inhibitors (e.g., ketoconazole, diltiazem) may increase plasma concentrations of aprepitant and result in an increased risk of adverse reactions related to CINVANTI.
  • Use of CINVANTI with strong CYP3A4 inducers (e.g., rifampin) may result in a reduction in aprepitant plasma concentrations and decreased efficacy of CINVANTI.

Hypersensitivity Reactions

Serious hypersensitivity reactions, including anaphylaxis, during or soon after administration of CINVANTI have occurred. Symptoms including dyspnea, eye swelling, flushing, pruritus, and wheezing have been reported. If hypersensitivity reactions occur, discontinue CINVANTI. Do not reinitiate CINVANTI in patients who experience these symptoms with previous use.

Decrease in INR with Concomitant Warfarin

Co-administration of CINVANTI with warfarin, a CYP2C9 substrate, may result in a clinically significant decrease in the International Normalized Ratio (INR) of prothrombin time. Monitor the INR in patients on chronic warfarin therapy in the 2-week period, particularly at 7 to 10 days, following initiation of CINVANTI with each chemotherapy cycle.

Risk of Reduced Efficacy of Hormonal Contraceptives

The efficacy of hormonal contraceptives may be reduced during administration of and for 28 days following the last dose of CINVANTI. Advise patients to use effective alternative or back-up methods of non-hormonal contraception during treatment with CINVANTI and for 1 month following administration of CINVANTI or oral aprepitant, whichever is administered last.

Use in Specific Populations

Avoid use of CINVANTI in pregnant women as alcohol is an inactive ingredient for CINVANTI. There is no safe level of alcohol exposure in pregnancy.

Adverse Reactions

The most common adverse reactions are:

  • Single-dose fosaprepitant with MEC (≥2%): fatigue, diarrhea, neutropenia, asthenia, anemia, peripheral neuropathy, leukopenia, dyspepsia, urinary tract infection, pain in extremity.
  • 3-day oral aprepitant with MEC (≥1% and greater than standard therapy): fatigue and eructation.
  • Single-dose fosaprepitant with HEC: generally similar to 3-day oral aprepitant. In addition, infusion site reactions (3%) occurred.
  • Single-dose CINVANTI (≥2%): headache and fatigue. The safety profile of CINVANTI in healthy subjects who received a single 2-minute injection was similar to that seen with a 30-minute infusion.

Report side effects to the FDA at 1-800-FDA-1088 or Report side effects to Heron at 1-844-437-6611.

For more information about CINVANTI, please see full Prescribing Information.

  1. ten Tije AJ, Verweij J, Loos WJ, Sparreboom A. Pharmacological effects of formulation vehicles: Implications for cancer chemotherapy. Clin Pharmacokinet. 2003;42(7):665-685.
  2. Coors EA, Seybold H, Merk HF, Mahler V. Polysorbate 80 in medical products and nonimmunologic anaphylactoid reactions. Ann Allergy Asthma Immunol. 2005;95(6):593-599.
  3. Pritchett W, Kinsley K. Benefits and risks of fosaprepitant in patients receiving emetogenic regimens. Clin J Oncol Nurs. 2016;20(5):555-556.
  4. Emend IV [prescribing information]. Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Whitehouse Station, NJ; January 2019.
  5. Cummings J, Forrest GJ, Cunningham D, Gilchrist NL, Soukop M. Influence of polysorbate 80 (Tween 80) and etoposide (VP-16-213) on the pharmacokinetics and urinary excretion of adriamycin and its metabolites in cancer patients. Can Chemo Pharm. 1986;17:80-84.
  6. Varubi [prescribing information]. Tesaro, Inc., Waltham, MA; January 2018.
  7. Excipients for drug formulation. Accessed January 25, 2019.
  8. Velagaleti R, Ku S. Accessed January 25, 2019.
  9. TESARO announces fourth-quarter and full-year 2017 operating results [news release]. Waltham, MA; TESARO, Inc.,the%20U.S.%20in%20April%202017.&targetText=Full%20year%202017%20total%20revenues,to%20%2458.0%20million%20for%202016. Accessed October 9, 2019.
  10. Lundberg JD, Crawford BS, Phillips G, Berger MJ, Wesolowski R. Incidence of infusion-site reactions associated with peripheral intravenous administration of fosaprepitant. Support Care Cancer. 2014;22(6):1461-1466.
  11. Leal AD, Kadakia KC, Looker S, et al. Fosaprepitant-induced phlebitis: a focus on patients receiving doxorubicin/cyclophosphamide therapy. Support Care Cancer. 2014;22(5):1313-1317.