Immunomodulation in Middle-Aged Humans Via the Ingestion of Physta® Standardized Root Water Extract of Eurycoma longifolia Jack--A Randomized, Double-Blind, Placebo-Controlled, Parallel Study

Phytother Res. 2016 Apr;30(4):627-35. doi: 10.1002/ptr.5571. Epub 2016 Jan 27.


This study was aimed to investigate the capacity of a standardized root water extract of Eurycoma longifolia (Tongkat Ali, TA), Physta® to modulate human immunity in a middle-aged Japanese population. This randomized, double-blind, placebo-controlled, parallel study was conducted for 4 weeks. Eighty-four of 126 subjects had relatively lower scores according to Scoring of Immunological Vigor (SIV) screening. Subjects were instructed to ingest either 200 mg/day of TA or rice powder as a placebo for 4 weeks [TA and Placebo (P) groups] and to visit a clinic in Tokyo twice (weeks 0 and 4). SIV, immunological grade, immunological age, and other immune parameters were measured. Eighty-three subjects completed the study; 40 in the TA group and 41 in the P group were statistically analyzed, whereas two were excluded from the analyses. At week 4, the SIV and immunological grade were significantly higher in the TA group than those in P group (p < 0.05). The numbers of total, naïve, and CD4(+) T cells were also higher in the TA group than those in P group (p < 0.05). No severe adverse events were observed. The results suggest that ingestion of the root water extract of TA (Physta®) enhances comprehensive immunity in both middle-aged men and women. This study is registered in UMIN-CTR (UMIN000011753).

Keywords: Scoring of Immunological Vigor; Tongkat Ali; comprehensive immunity; eurycomanone.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Double-Blind Method
  • Eurycoma / chemistry*
  • Female
  • Humans
  • Immune System / drug effects*
  • Immunomodulation*
  • Male
  • Middle Aged
  • Plant Extracts / therapeutic use*
  • Plant Roots / chemistry
  • T-Lymphocytes / drug effects
  • Water / chemistry


  • Plant Extracts
  • Water

Associated data

  • JPRN/UMIN000011753