FDA’s Public Availability of: Draft Environmental Assessment and Preliminary Finding of No Significant Impact Concerning Investigational Use of Oxitec OX513A Mosquitoes

May 13, 2016

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The Florida Keys Mosquito Control District (FKMCD) first consulted with Oxitec regarding its genetically modified (GM) OX513A mosquito for population control due to public health concerns about the spread of mosquito-borne diseases when 22 people in Florida’s Key West were diagnosed with Dengue fever in 2009 and 66 in 2010. The FKMCD decided to test the effectiveness of OX513A by allowing Oxitec to conduct a field trial in Key Haven, Florida. The FKMCD is particularly concerned with the potential for Aedes aegypti to act as a vector for the transmission of diseases such as Dengue and Chikungunya, and most recently Zika virus. Although they have decades of expertise in combating mosquitos, several factors—including reductions in the effectiveness of insecticide use due to populations gaining resistance—result in an estimated maximum population reduction of 50% at best.[1] Field trials conducted in Brazil[2] and the Cayman Islands[3] estimate the effectiveness of OX513A around 90%, which would significantly decrease the risk of disease transmission[4] at potentially lower cost.

Oxitec’s field trial has awaited FDA approval since 2011. As part of its approval process the FDA is required by the National Environmental Policy Act (NEPA) to assess Oxitec’s submission of an environmental assessment (EA) and consider whether the evidence indicates that the trial could have a significant impact on the environment. FDA, in consultation with the Centers for Disease Control and Prevention (CDC) and the Environmental Protection Agency (EPA) has published and made available to the public for comment a preliminary Finding of No Significant Impact (FONSI). Unless the public’s input demonstrates any scientific evidence or area of consideration that FDA and its interagency group has not already considered, FDA will proceed to publish a final FONSI, allowing Oxitec to begin its field trial.

Evidence supports the interagency opinion that there is no appreciable risk to human or animal health or the environment. Further delays in allowing the field trial to be conducted or approving OX513A for commercial use in the U.S., pending the submission of data from a successful field trial, will continue to constrain the options available to limit the spread of mosquito-borne diseases and unnecessarily exposes the public to increased levels of risk—particularly in the event of an outbreak.

The unusually lengthy timeframe for FDA approval of this field trial in comparison to similar trials routinely approved by the USDA for the control of pests has already limited the number of effective tools available to combat the spread of dangerous diseases such as Zika, Dengue, and Chikungunya.

Statutory Authority

No laws specifically address the regulation of GM animals. Rather, U.S. agencies have successfully regulated GM products under their existing statutory framework since the Office of Science and Technology Policy (OSTP) issued the Coordinated Framework for Regulation of Biotechnology (CF) in 1986.[5] Both USDA and FDA currently regulate genetically modified insects. USDA claims authority over GM insects considered “pests” under either the Plant Protection Act[6] or the Animal Health Protection Act.[7] To be considered a pest an insect must directly or indirectly injure, cause damage to, or cause disease in livestock or plants.

If it is not a pest, FDA claims jurisdiction over the GM insect. The Federal Food, Drug, and Cosmetic Act (FD&C) defines “articles (other than food) intended to affect the structure or any function of the body of man or other animals” as drugs. [8] Therefore, FDA currently regulates GM animals—including insects—under its interpretation that modified rDNA is a drug.[9] Since a “new animal drug” is “any drug intended for use for animals other than man,” and since mosquitoes are not considered plant or livestock pests, FDA considers Oxitec’s application for approval of its field trial of OX513A an Investigational New Animal Drug (INAD).[10] Pursuant to FDA regulations, sponsors opening a new INAD file must submit either a draft EA or claim categorical exclusion from the EA requirement.[11] Oxitec requires FDA approval before initiating a field trial because the FD&C Act makes it otherwise unlawful to introduce new animal drugs into commerce.

Oxitec’s application to conduct its field trial in Key Haven, Florida has caused a significant amount of controversy, with many citizens arguing against releasing a GM insect to reduce mosquito populations. However, it should be noted that USDA scientists pioneered the use of releasing sterile insects for population control, known as the Sterile Insect Technique (SIT), more than 70 years ago and the agency has approved releases for more than 50 years with many documented successes. Among them is the eradication of the screwworm fly in North and Central America in 1966 which proceeded without any evidence of harm to the environment or humans. Incidentally, the first field test for using SIT was conducted in Florida on Sanibel Island.