Companies hope to genetically modify plants such as tobacco to produce medicines. Credit: GETTY

Commercial development of plant-derived pharmaceuticals has moved forward today with the publication of the first European guidelines for growing these genetically modified (GM) plants.

Drawn up by the European Food Safety Authority (EFSA), based in Parma, Italy, the guidance describes how developers of GM plants grown for purposes other than human or animal consumption, such as producing pharmaceuticals or industrial enzymes, will need to assess the potential risks to humans, animals and the environment.

An EFSA risk assessment will be required when developers seek commercial approval to grow the plant. The evaluation will be passed on to the European Commission and member states, which decide whether to grant permission. In contrast, scientists wishing to grow GM crops for research purposes need only apply for a licence in the individual member state in which they wish to grow the crop.

On your marks

Reinhilde Schoonjans, scientific officer on the EFSA's Scientific Panel on Genetically Modified Organisms, says the agency has not yet received any applications for plants modified to produce drugs. Internationally, only a handful of clinical trials of such drugs are under way, and there are no plant-pharmed drugs on the market. But, Schoonjans says, the technology is progressing fast and the EFSA is now in a position to receive applications — likely to come mostly from university spin-offs. "We want to be ready," she says.

The EFSA will only consider the risks of growing the GM plant. The safety of the plant's product will be considered by the European Medicines Agency (EMEA), which has guidelines on the safety and quality requirements of plant-derived drugs that came into effect in February.

Under the EFSA guidance, developers must detail the biological differences between the GM plant and the conventional crop it is derived from and how these affect the plant's function and growth. They also have to assess the risk of engineered genes being passed on to other plants and any danger posed to humans or animals who accidentally eat the transgenic crops.

Applicants must also specify the measures they will take to monitor the plants and protect against exposure — such as warning signs, fences and sterilization of the plants to prevent them reproducing.

Strict rules

"It replaces what we had before, which was nothing, so that is a positive step," says Julian Ma, a molecular immunologist at St George's Hospital Medical School, University of London, who helped to draw up the guidelines.

He says that the guidelines are based on existing GM-food regulation, which imposes strict rules on managing unintended effects from GM plants. These rules are not mirrored in conventional agriculture, where there are also unintended effects, Ma says.

For instance, there is "no scientific rational" for requiring the rigorous testing of a plant genetically modified to produce a toxic substance, Ma says, but not requiring the same tests of a plant bred through traditional methods to produce the same toxic compound. "We struggled with this," he says.

Jeffrey Wolt, an expert in plant biotechnology risk assessment at Iowa State University in Ames, approves of the European guidelines and says they are consistent with those set out by the US Food and Drug Administration and Department of Agriculture.

He is pleased that the guidelines will consider each application on a case by case basis. "This is critical," he says, "because when you are working with an emerging area of science such as this, a too prescriptive process would be counter productive."