CSIR publishes Hoodia clinical studies

The CSIR has published a synopsis on the clinical studies done on Hoodia during the period 1999 to 2003.

Hoodia plant in flower
Hoodia plant in flower

Dr Vinesh Maharaj, a Technology Manager at the CSIR, said: “It is important to publish these clinical studies for public awareness.” The CSIR has also acquired the reports to 14 clinical studies in which Hoodia has been assessed, using crude extracts and concentrated active ingredients formulated in a number of different ways. In many of these studies Hoodia was found to be generally safe and well tolerated, though in some subjects adverse events and tolerability issues were noted with the concentrated active ingredient extracts.”

“The clinical studies during the period 1999 to 2003 were performed on a spray-dried sap extract and a concentrated active ingredient extract, both formulated as capsules. In the safety studies, the spray-dried sap extract was shown to be safe and well tolerated at all dosages while some level of efficacy including caloric reduction was observed at the higher dosages. In a 14-day repeat dose study using the extract, there was a good safety and tolerance profile, however no signs of efficacy were observed mainly due to the low dosage.”

“This was not surprising considering that some levels of efficacy in the safety studies were observed at higher dosages suggesting that future development should focus on the formulation of higher doses of the spray-dried sap extract. In a 5 and 15-day repeat dose study using the concentrated active ingredient extract there was a clear anorectic effect and a substantial reduction in caloric intake compared to the placebo.”

“In the 15-day repeat dose study there were mild side effects such as taste perversion and isolated reversible hyperbilirubinaemia (excess of bile pigment in the blood). There were no signs of abnormal ECG, vital signs or physical examination findings during the study. The exaggerated effect on caloric intake suggests lower dosage levels for further evaluation of the concentrated extract in a solid formulation,” added Dr Maharaj.

A full synopsis of the findings of these is made available through the CSIR web-based research space and includes the following:

    1. A single Phase I, double-blind, placebo-controlled, ascending single oral dose, safety, tolerability and pharmacokinetic study in obese male subjects using a spray-dried extract of Hoodia as the active substance formulated as capsules (coded P57FP). The study intended to include both male and female, but only males were enrolled.
    2. A Phase I, double-blind, placebo-controlled, single ascending oral dose study to investigate the safety, tolerability, pharmacokinetics and pharmacodynamics of a spray-dried extract of Hoodia formulated into capsules (coded P57FP) in male volunteers.
  • A Phase I, placebo-controlled, 14-day repeat dose study in an ascending dose parallel group design to establish the safety, tolerability and effects of a spray-dried extract of Hoodia formulated into capsules (coded P57FP) in suppressing appetite in non-patient male volunteers.



  • A randomised, double-blind, placebo-controlled, 15-day repeat dose study, with a single dose escalation stage, to establish the pharmacokinetics, safety, tolerability and effects of the concentrated spray-dried extract (coded PYM50027) in healthy male subjects.



  • An independent expert review of laboratory data from Hoodia studies.


“Commercialisation of Hoodia gordonii as a dietary supplement has created major interest around the world and further development of Hoodia as a functional food for management of weight remains important,” said Dr Maharaj.

“The development going forward requires clinical studies which are typically multi-million rand investments. The clinical studies have not been scoped yet, so no precise budgets are available at this stage. The CSIR does not have a budget for further development at this stage – as is typical of the model for funding projects of this nature in the National System of Innovation, the CSIR will engage with all stakeholders, public funding institutions and potential licensees to support further development. Funds are allocated on properly motivated, stage gated applications with detailed plans,” he added.

When the CSIR signed a cooperation agreement with Phytopharm, a United Kingdom-based pharmaceutical development company in November 2010 for the further development and commercialisation of Hoodia gordonii , the CSIR acquired the rights to substantial know-how and IP developed when the former license agreement was in place. During this time, many technical issues around the agronomy, extraction of the active ingredients, and other processing or manufacturing related challenges were resolved.

Story: CSIR e-News, December 2011