Biologics

Biological Products

The defining difference from small molecules is that a biologic is defined by its process. A synthetic drug substance can be fully characterised analytically and reproduced from its structure; a monoclonal antibody or cell therapy carries product-related variants — glycosylation, aggregation, charge variants — that analytics can describe but not fully specify. Change the process and you may change the product, which is why "the process is the product" remains the working rule.

That drives three preoccupations. Characterisation: an extensive orthogonal analytical package, because no single method captures the molecule. Viral and adventitious-agent safety: control of cell banks and raw materials plus validated clearance steps, per ICH Q5A(R2). And comparability: any manufacturing change must be shown, under ICH Q5E, not to have adversely affected quality, safety, or efficacy — sometimes analytically alone, sometimes requiring clinical data.

The category is broad and getting broader — therapeutic proteins, vaccines, blood and plasma products, allergenics, tissues, and advanced therapies (gene and cell therapy). Cold-chain integrity, potency assays that measure biological activity rather than chemical content, and immunogenicity risk are practical concerns that simply do not arise for a conventional tablet.

• —Process-defined: manufacturing changes can change the product, so change control carries unusual weight.
• —Characterisation needs an orthogonal analytical package — no single method is sufficient.
• —Viral safety rests on cell-bank and raw-material control plus validated clearance (ICH Q5A(R2)).
• —Comparability after change is a formal exercise under ICH Q5E, not an assumption.
• —Potency is a measure of biological activity; immunogenicity and cold chain are routine concerns.

US: Public Health Service Act §351 (BLA) and 21 CFR Parts 600–680; EU: Directive 2001/83/EC Annex I Part III and Regulation (EC) No 1394/2007 for advanced therapies; ICH Q5A(R2) (viral safety), Q5E (comparability), and Q6B (specifications for biotechnological products).