GMO pharma crop drug successes limited; monoclonal antibody drugs can be risky

There's been a flurry of press articles around an experimental drug which has had promising initial results in treating Ebola virus infection in two American aid workers who contracted the disease in Africa.

The drug, called ZMapp, is derived from GM tobacco and is hyped on one science blog as "fairly cheap, readily up-scalable" way to treat Ebola.

The treatment, which had been tested only in lab animals before being given to the two American medical workers in Liberia, consists of proteins called monoclonal antibodies that bind to and inactivate the Ebola virus.

A study published last year showed that 43 percent of infected primates given the drug recovered.

However, even if the two treated aid workers recover, much more study is needed to confirm whether the drug works in general, said Dr Thomas Frieden, head of the US Centers for Disease Control and Prevention. Two patients is far too small a sample to form conclusions, said Frieden.

US President Barack Obama has said it is "premature" to send experimental drugs for the treatment of Ebola to West Africa, which has been hardest hit by the deadly outbreak.

Obama said affected countries should focus on building a "strong public infrastructure," adding: "I think we have to let the science guide us... I don't think all the information is in on whether this drug is helpful."

Obama's precaution seems sensible in light of the fact that ZMapp is a GM monoclonal antibody drug. Monoclonal antibodies are disease-fighting proteins that target a specific part of an invading pathogen, in this case the Ebola virus.

Several years ago another GM monoclonal antibody drug produced horrific reactions, including organ failure, in the six healthy young men who volunteered to trial it. It was dubbed "the Elephant Man drug" because the head of one of the subjects swelled up.

Other monoclonal antibody drugs are known to cause serious side-effects, though clearly, if a drug offers a chance of life to someone who would otherwise die, as in the Ebola cases, that consideration would weigh heaviest in the balance.

GM pharma crop drug successes limited

As for the record of GM "pharma" crops engineered to produce drugs, successes are extremely limited, according to an article for Reuters.

In 2012 the FDA okayed a drug for the rare genetic disorder Gaucher disease from Israel's Protalix BioTherapeutics and Pfizer. Called Elelyso, it is made in carrot cells, and is the only such drug to reach the market.

Calgary-based SemBioSys Genetics Inc, which used safflowers to produce an experimental diabetes drug, folded in 2012 before it finished clinical trials.

Even Kentucky Bioprocessing, which at one point was developing monoclonal antibodies against HIV (the virus that causes AIDS), C. difficile bacterial infection, and the human papilloma virus, has dropped the last two projects, according to David Howard, a spokesman for tobacco giant Reynolds American, which owns Kentucky Bioprocessing. Kentucky Bioprocessing also produced the GM tobacco plants for the Ebola therapy.

And in spite of the science blogger's claim that the new Ebola drug is "readily up-scalable", for the moment, there are "virtually no doses available", according to the US Centers for Disease Control and Prevention.

GMWatch position on GM "pharma" crops

We have no problem with the medical use of GM technology as long as products are developed in properly contained settings and tested and used responsibly. Also we do not oppose experimental use of GM medical applications without prior trials in extreme situations like the Ebola cases where there are no alternatives on offer – provided informed consent to the experimental treatment is obtained from the patient and/or their next of kin.

By contrast, we consider the production of pharmaceuticals in GM food crops, like maize, in non-contained settings to be extremely irresponsible and we oppose this without exception. The point about medicines is that
* Only the person taking them should be exposed to them
* Informed consent must be gained to the treatment
* You have to be able to control the dose.

GM pharma food crops grown in the open potentially violate all three principles.

Tobacco is obviously not a food plant but people smoke it and could be exposed to pharmaceuticals via inhalation. Also an environmental risk assessment would have to be carried out to see how GM pharma tobacco would affect non-target organisms like insects. However, the GM tobacco used in this Ebola drug appears to have been produced in a contained environment (in greenhouses).

If this is the case, we applaud the developer company for observing that precaution, which should be a regulatory requirement for all GM pharma crops.

(Comment by Claire Robinson)