Contract manufacturing of solid dosage forms

In brief

Solid dosage forms are mainly tablets, film-coated tablets, capsules, granules and powders. They make up a large share of oral medicines and are manufactured with processes that have proven themselves over many years: weighing and blending the starting materials, granulating and drying, compressing into tablets, film coating or filling into hard capsules. The manufacturing is still not simple, because even small differences in raw materials or process parameters can change the content, uniformity and release of the active substance.

In contract manufacturing, a contract manufacturer takes over all or some of these steps for the owner of the product, often including packaging. Both parties set out in a written contract which obligations lie with whom. The contract giver remains responsible for controlling the outsourced manufacturing.

When you need this

Typical contract givers are companies that have developed or in-licensed a product and do not run their own manufacturing, and manufacturers whose equipment is not designed for a particular process. That may be a wet granulation, a modified-release coating or the processing of a highly potent active substance that requires closed equipment. A transfer to a contract manufacturer also becomes necessary when in-house capacity is no longer sufficient for a growing product or when a site is closed.

In clinical development, small batches are often needed for trials while the formulation is still changing. Manufacturers with smaller equipment and development experience are suited to this, whereas larger batches and a stable supply chain count later for commercial supply.

Legal basis and rules

Anyone in Germany who manufactures medicinal products commercially or professionally needs a manufacturing authorisation under Section 13 AMG, which under Section 16 AMG applies to a specific site and to specific medicinal products and dosage forms. Check therefore whether your manufacturer’s authorisation explicitly covers your dosage form. The AMWHV obliges the site to follow Good Manufacturing Practice and refers to the EU GMP Guide for its interpretation.

Dust and cross-contamination

The core risk with solid dosage forms is dust. Chapter 3 of the EU GMP Guide requires specific provisions wherever dust is generated during sampling, weighing, mixing, processing or packaging of dry products, to avoid cross-contamination and to facilitate cleaning. According to Chapter 5, the extent of the measures follows from a quality risk management process that includes an evaluation of the potency and toxicology of the products manufactured. This determines whether individual product-contact parts or entire facilities must be dedicated to one product. Under Chapter 3, dedicated facilities are required if the risk cannot be controlled by technical or organisational measures, if the toxicological evaluation does not support a controllable risk, for example with highly sensitising materials such as beta-lactams, or if the derived residue limits cannot be determined with a validated method.

Validation of process and cleaning

Under Annex 15, every manufacturer must determine and justify the number of validation batches based on quality risk management. For traditional process validation, a minimum of three consecutive batches manufactured under routine conditions is generally considered acceptable. A different number may be justified, for example by whether standard manufacturing methods are used and whether the site already manufactures similar products or processes. The first three batches may need to be supplemented with data from subsequent batches as part of ongoing process verification. For products developed by a quality by design approach, Annex 15 also allows continuous process verification instead of traditional validation. For shared equipment, cleaning validation is also decisive, and its limits for product carry-over should be based on a toxicological evaluation.

How the collaboration works

The collaboration is governed by Chapter 7 of the EU GMP Guide: the contract giver first assesses whether the contract acceptor is legally authorised, suitable and competent, and then monitors its performance on an ongoing basis. In practice the path usually looks like this:

What to look for when selecting a manufacturer

You can use the following questions to compare providers and to follow up specifically during the audit.

Frequently asked questions

Sources

Every statement in this text was checked against these primary sources (as of 10.11.2026). Laws, guidelines and authority websites, no advertising.

1. EU-Kommission (EudraLex) · vol4-chap7_2012-06_en_0.pdf
2. Gesetze im Internet · __13.html
3. Gesetze im Internet · __16.html
4. Gesetze im Internet · __3.html
5. Gesetze im Internet · __9.html
6. EU-Kommission (EudraLex) · eudralex-volume-4_en
7. EU-Kommission (EudraLex) · 18d76565-137b-41d2-a602-794527f708c1_en
8. EU-Kommission (EudraLex) · 4a1fdb4f-6f6f-49c4-b264-8056e5bbe078_en
9. EU-Kommission (EudraLex) · 2015-10_annex15_0.pdf
10. EU-Kommission (EudraLex) · reg_2016_161_en_0.pdf