What are the steps that needs to be fllowed for testing a new drug?

<< Prev 4 of 26 in Topic Next >>

Topic : New Drugs Value Creation

Rate :

Posted in Community :

Regulatory Compliance Management in life sciences industry

	What are the steps that needs to be fllowed for testing a new drug? Asked by : Pratibha Rana, Product/Brand Manager, Dr Reddy Labs Industry : Pharmaceuticals Functional Area : Innovation Keywords : Needs Steps Testing Drug FLLOWED Activity: Question posted: 05 09 2008 04:22:55 +0000, 2 answers, 242 views, last activity 07 06 2010 20:18:08 +0000	Answer

Refer 0

The clinical investigation of a previously untested drug is generally divided into three phases. Although in general the phases are conducted sequentially, they may overlap. The three phases of an investigation are as follows:

Phase 1; includes the initial introduction of an investigational new drug into humans. These studies are usually conducted in healthy volunteer subjects. These studies are designed to determine the metabolic and pharmacological actions of the drug in humans, the side effects associated with increasing doses, and, if possible, to gain early evidence on effectiveness. Phase 1 studies also evaluate drug metabolism, structure-activity relationships, and the mechanism of action in humans. The total number of subjects included in Phase 1 studies is generally in the range of twenty to eighty.

Phase 2 includes the early controlled clinical studies conducted to obtain some preliminary data on the effectiveness of the drug for a particular indication or indications in patients with the disease or condition. This phase of testing also helps determine the common short-term side effects and risks associated with the drug. Phase 2 studies usually involve several hundred people.

Phase 3 studies are intended to gather the additional information about effectiveness and safety that is needed to evaluate the overall benefit-risk relationship of the drug. Phase 3 studies also provide an adequate basis for extrapolating the results to the general population and transmitting that information in the physician labeling. Phase 3 studies usually include several hundred to several thousand people.

Report Abuse

by Ajoy Mondal, Product/Brand Manager, Ranbaxy Labs | 05 09 2008 04:25:01 +0000

go to top

2 Answers for "What are the steps that needs to be fllowed for testing a new drug?"

Sort by: Most Recent Top Rated

Prev1NextShowing 1 - 1 of 2

Answered by Bindu Narayan, Product Development Manager, Care Biomedicals | 05 05 2009 10:19:40 +0000

Report Abuse

Not Rated

Thousands of chemicals, both synthetic and extracted from "natural" sources, are being examined in the hope of finding new drugs with which to combat human and veterinary diseases.

The first step is to use laboratory tests to find if these substances have a significant effect on, for example:

cells growing in tissue culture

laboratory animals such as rats and mice.

If the drug achieves the desired effect in laboratory animals, without killing them in the process, the drug developer applies to the U. S. Food and Drug Administration for an IND, an investigational new drug application. Granting of an IND allows testing in humans to begin. This occurs in three phases

.

Phase I

A small group (20–100) of healthy volunteers is given the drug to see

if it is safe
how quickly it is absorbed, metabolized, and excreted from the body

Phase II

A group (up to several hundred) of volunteer patients with the disease are given the drug to see

how effective it is against the signs and symptoms of the disease
what doses are best
what side effects may occur

A control group of similar size is given a dummy drug (placebo). Ideally the trials are "blinded" with neither the subjects (nor the investigator) knowing which pill a subject is receiving.

Phase III

Hundreds to thousands of patients with the disease are given the drug to get more reliable data on its

effectiveness
safety
best dose
rare side effects

all compared with the drug(s) that are currently used for the disease.

If all goes well, the drug manufacturer applies to the Food and Drug Administration for an NDA, a new drug application. If it is granted, the generic name of the drug is replaced by a brand name chosen by the manufacturer. For example, one of the first drugs used against AIDS was azidodideoxythymidine (AZT). When placed on the market, this name was replaced by the brand name zidovudine.

Phase IV

Even after a drug is available for prescription, its use is carefully monitored and unexpected side effects are reported. Continuing oversight of an approved drug is called postmarketing surveillance or Phase IV trials.