Liver Enzyme Elevations in Plasmodium falciparum Volunteer Infection Studies: Findings and Recommendations

Am J Trop Med Hyg. 2020 Jul;103(1):378-393. doi: 10.4269/ajtmh.19-0846. Epub 2020 Apr 16.

Abstract

Malaria volunteer infection studies (VISs) accelerate new drug and vaccine development. In the induced blood-stage malaria (IBSM) model, volunteers are inoculated with erythrocytes infected with Plasmodium falciparum. Observations of elevated liver enzymes in the IBSM model with new chemical entities (NCEs) promoted an analysis of available data. Data were reviewed from eight IBSM studies of seven different NCEs, plus two studies with the registered antimalarial piperaquine conducted between June 2013 and January 2017 at QIMR Berghofer, Brisbane, Australia. Alanine aminotransferase (ALT) was elevated (> 2.5 times the upper limit of normal [×ULN]) in 20/114 (17.5%) participants. Of these, 8.9% (10/114) had moderate increases (> 2.5-5 × ULN), noted in seven studies of six different NCEs ± piperaquine or piperaquine alone, and 8.9% (10/114) had severe elevations (> 5 × ULN), occurring in six studies of six different NCEs ± piperaquine. Aspartate aminotransferase (AST) was elevated (> 2.5 × ULN) in 11.4% (13/114) of participants, across six of the 10 studies. Bilirubin was > 2 × ULN in one participant. Published data from other VIS models, using sporozoite inoculation by systemic administration or mosquito feeding, also showed moderate/severe liver enzyme elevations. In conclusion, liver enzyme elevations in IBSM studies are most likely multifactorial and could be caused by the model conditions, that is, malaria infection/parasite density and/or effective parasite clearance, or by participant-specific risk factors, acetaminophen administration, or direct hepatotoxicity of the test drug. We make recommendations that may mitigate the risk of liver enzyme elevations in future VISs and propose measures to assist their interpretation, should they occur.

MeSH terms

  • Acrylamides / adverse effects
  • Adamantane / adverse effects
  • Adamantane / analogs & derivatives
  • Adult
  • Alanine Transaminase / metabolism*
  • Aminopyridines / adverse effects
  • Aminoquinolines / adverse effects
  • Antimalarials / adverse effects*
  • Aspartate Aminotransferases / metabolism*
  • Chemical and Drug Induced Liver Injury / epidemiology*
  • Chemical and Drug Induced Liver Injury / etiology
  • Chemical and Drug Induced Liver Injury / metabolism
  • Erythrocyte Transfusion
  • Erythrocytes / parasitology
  • Female
  • Ferrous Compounds / adverse effects
  • Healthy Volunteers*
  • Heterocyclic Compounds, 4 or More Rings / adverse effects
  • Humans
  • Indoles / adverse effects
  • Isoquinolines / adverse effects
  • Malaria, Falciparum / drug therapy*
  • Male
  • Metallocenes / adverse effects
  • Parasitemia / drug therapy*
  • Peroxides / adverse effects
  • Piperazines / adverse effects
  • Plasmodium falciparum
  • Primaquine / adverse effects
  • Pyrimidines / adverse effects
  • Quinolines / adverse effects
  • Spiro Compounds / adverse effects
  • Sulfones / adverse effects
  • Triazoles / adverse effects
  • Young Adult

Substances

  • ACT-451840
  • Acrylamides
  • Aminopyridines
  • Aminoquinolines
  • Antimalarials
  • Ferrous Compounds
  • Heterocyclic Compounds, 4 or More Rings
  • Indoles
  • Isoquinolines
  • MMV390048
  • Metallocenes
  • NITD 609
  • Peroxides
  • Piperazines
  • Pyrimidines
  • Quinolines
  • SJ733
  • Spiro Compounds
  • Sulfones
  • Triazoles
  • DSM265
  • ferroquine
  • piperaquine
  • Aspartate Aminotransferases
  • Alanine Transaminase
  • Primaquine
  • Adamantane
  • artefenomel