While the US FDA is in the process of implementing CGMP standards mandatory for Positron Emission Tomography (PET) drugs, the Indian drug control authorities do not even directly monitor the same drugs manufactured in Indian as in the case of medical devices.

In India, the Board of Radiation and Isotope Technology (BRIT), part of the Bhabha Atomic Research Centre, manufactures all the drugs used for the radiopharmaceutical purposes, apart from a few research units, which are said to develop it in small scale for in-house laboratory activities. The drugs used for PET, Radiochemicals, Radiopharmaceuticals, sealed sources, radiation sources, labelled compounds and other allied products come under the purview of a Radio Pharmaceutical Committee, selected by the chairman of Department of Atomic Energy (DAE). The committee consists of doctors including nuclear medicine doctors, pharmacists, research scientists etc. along with a representative from Drug Control General of India (DCGI) and Maharashtra Food and Drug Administration (FDA).

PET is a medical diagnostic tool in which a radioactive drug is administered to a patient, most commonly by intravenous injection, and the distribution and uptake of the radioactive drug to various bodily organs is imaged using a special camera (also called a scanner). The image helps physicians diagnose diseases such as cancer and heart disease. PET images show biochemical changes of an organ or tissue in the human body, unlike X-ray, CT, or MRI images that show only body structures.

When contacted by Pharmabiz to know the Indian situation following the US FDA move, BRIT sources said the PET drugs manufactured in India conform to the standards set up by the Radio Pharmaceutical Committee. “BRIT has a full-fledged Quality control department, Standard Operating Procedures (SOP) and other facilities to check the quality of the drugs used for the radiation treatment. The drugs are allowed to be used for the medical purposes only after a screening by the Radio Pharmaceutical Committee,” said Dr. N Sivaprasad, General Manager, BRIT.

Sources however noted PET drugs have a short half-life, as it decay with time and must be used within hours or minutes after production. This characteristic affects how they are produced and as a result, some of the CGMP requirements for traditional pharmaceuticals are not necessary or appropriate for the production of PET drugs.

Last week, the US FDA announced its plans to implement Current Good Manufacturing Practices (CGMP) regulation for the production of Positron Emission Tomography (PET) drugs. The regulation is intended to ensure that PET drug products meet the requirements of the Federal Food, Drug, and Cosmetic Act (FD&C Act) as to safety, identity, strength, quality, and purity. Concurrently with the issuance of this proposed regulation, FDA has also published a draft guidance entitled "PET Drug Products - Current Good Manufacturing Practice (CGMP)"

Further, FDA has also simplified the approval procedures for some commonly used PET drugs by publishing findings regarding their safety and efficacy upon which PET producers could rely in submitting new drug applications, and publishing guidance that explains in detail how to submit an application. FDA is also publishing the proposed CGMPs for comment. After the comment period closes, FDA will prepare a final rule that includes responses to the comments. Two years after that final rule takes effect, PET producers will be required to submit new drug applications before marketing a PET drug.

Sources said PET is an important tool for understanding the brain chemistry. It is expected that PET will aid the understanding of the chemistry of many psychiatric diseases. PET is capable of visualizing changes in neurotransmitters and neuroreceptors and their interaction more precisely than any other modality of imaging such as CAT or MRI. One PET drug in particular, known as Fludeoxyglucose or [F18] FDG, has been shown to be useful in identifying active tumors, for monitoring the progression or regression of malignancies, and for monitoring the effectiveness of therapeutic interventions.