Generic pharmaceutical drug development

Generic pharmaceutical drug development
A generic pharmaceutical drug is a drug that contains the same
chemical composition as the drug which was protected by chemical
patents. The generic drug product development’s main steps include
characterization of the reference product, design of a bioequivalent
product, and bioequivalent study. Let’s study the process in detail:
Before development
At first, the product which is to be developed is selected. To make a
proper selection, the input is needed from a variety of disciplines such
as:
● R and D
Regulatory Affairs
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● Legal
Marketing and sales
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Finance etc.
After selecting the right product, its details are recorded in a
document that includes information like:
Product Description and Dosage form
product packaging Description
Innovator product sales
Generic product description
Generic sales forecast
Intended manufacturing site
Other relevant information
Based on the patent’s expiry, availability of ingredients, etc., the
project is scheduled, and the progress is tracked and managed.

Pre formulation
Before the actual trial formulations, pre-formulation is done to gain
information about the drug substance.
Their activities include:
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Review of the selected product document
Gathering samples of the reference product
Evaluating the physical characteristics of the product.
Determining reference drug release characteristics
Characterization of the drug to determine the form of the drug
Based on these activities, decisions are made according to the
formulation type and process of development. The reference product
itself determines the dosage form and strength.

Three processes are carried out. They are:
- Direct mixing: The drug substances are directly blended with
the excipients. Then the mixture is either compressed into tablets
or filled into capsule shells.
- Dry granulation: The drug substances are processed with
the excipients using a slugging technique. This is followed by
granulation sizing. Finally, the additional excipients are blended
with the product. It is then compressed into tablets or filled into
capsule shells.
- Wet granulation: In this process, the drug substance is
processed with the excipients. Then the binder is mixed with a
solvent to form a granulation that is dried and blended with
additional excipients. After that, the final mixture is either blended
into tablets or filled into capsules.
Whenever possible, direct mixing is initiated because his process is the
most straightforward and economical means to produce solid
pharmaceutical dosage.
The following ingredients are included in a tablet or capsule dosage:
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Chemically active ingredients
Binder which helps to hold drug particles to form tablets or capsule
slugs
Solvent for undergoing wet granulation
A disintegrating agent which helps to break apart the granules and

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tablets for dissolution and absorption
Anti-adherent which works as a lubricant
A lubricant prevents the powders from sticking to the equipment
used to compress tablets.
There are some other ingredients as well;
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Dyes which impart a color to the tablet
Sweetening agents which add flavors
Wetting agents to enhance the solubility of the drug substance
Acidifying agents and buffers which provide a more stable
environment to the drug product.
After pre-formulation work and development are completed, small scale
trials are performed. During the trials, the drug substance is processed
with the excipients to produce a dired strength and appearance dosage.
The dosage is then physically and chemically evaluated. This
determines its acceptability.
Some of the common types of testing performed on the tablets and
capsules are:
- Physical testing like appearance, weight variation, time of
disintegration, etc.
- Chemical testing like chemical identification, dissolution profiles
vs. reference product, etc.
If the product retains good physical and chemical properties, it is sent
for the test of “in-vivo bioequivalency” vs. reference product. If it proves
to be bioequivalent to the reference product, a package is assembled

and submitted to the respective government regulatory agency who
reviews the product and approves it eventually. A successfully
developed generic product requires bioequivalence study, approval, and
product validation study. Spending more time, planning, and effort
during generic drug development will generate the type of desired
robust products.