Generics are medicinal products that contain the same active substance in the same strength and dosage form as a reference medicinal product. The objective is to provide a therapeutically equivalent alternative after the expiry of patent and data protection, usually at a lower cost. In Europe, the authorization of generics is achieved through a dedicated, simplified procedure in which clinical efficacy studies are mostly replaced by bioequivalence data.
Definition and Scope
A generic product is based on an active substance whose quality, safety, and efficacy have already been proven by the reference product. The generic application therefore relies largely on publicly available data and “bibliographic” knowledge of the active substance, supplemented by product-specific evidence. Generics must be distinguished in particular from biosimilars: while generics are typical for chemically defined small molecules, biosimilars concern biologically produced complex molecules where an extended comparability study is required.
In practice, a distinction is also made between “branded generics” and products identified solely by the name of the active substance. For the assessment in the marketing authorization procedure, however, this marketing distinction is generally irrelevant. In daily market practice, it can be relevant if prescribers, hospital pharmacies, or tenders reflect specific provider preferences.
Authorization Pathways in the EU and Germany
The legal basis in the EU is primarily Directive 2001/83/EC (human medicinal products) and, additionally, Regulation (EC) No 726/2004 for the centralized procedure. For generics, a so-called “abbreviated application” (generic application) is frequently used, in which the focus is on proving bioequivalence to the reference product. In Germany, national processing is typically carried out by the BfArM or the Paul Ehrlich Institute, depending on the product class.
Depending on the product and market strategy, the national procedure, the decentralized procedure (DCP), or the mutual recognition procedure (MRP) may be considered. For active substances subject to the centralized procedure (e.g., certain biotechnology products), a generic in the strict sense is usually not possible; in such cases, biosimilar-specific pathways would need to be examined. From a project perspective, this means that the appropriate target markets, reference products, and dossiers must be defined as early as the initial regulatory strategy phase.
Bioequivalence and Clinical Data
The core of the generic concept is the assumption of therapeutic equivalence upon proven bioequivalence. Usually, pharmacokinetic studies are conducted in healthy volunteers, comparing parameters such as AUC and Cmax. Acceptance ranges (often 80–125% for the 90% confidence interval) are described in relevant guidelines. For certain dosage forms (e.g., inhalable products, topical applications), proof can be more demanding and may require additional in vitro or clinical data.
From the perspective of the sponsor and CRO, the sound planning of the bioequivalence program is crucial: the protocol, statistical power, study logistics, bioanalytics, and data integrity must align. Common sources of error include insufficient control of food effects, non-standardized sampling windows, or unclear handling of outliers, which can lead to regulatory queries and delays. In practice, a transparent derivation of the sample size and early coordination with bioanalytical laboratories (assay validation, sample stability, chain of custody) are also important.
Quality, Manufacturing, and Pharmacovigilance
The following also applies to generics: the quality of the finished medicinal product must be ensured in accordance with Good Manufacturing Practice. Critical aspects include specifications, validation of manufacturing processes, stability data, and the control of impurities (e.g., nitrosamines). The active substance supplier and the supply chain are subject to regulatory assessment; changes can trigger variation procedures. For marketing authorization and lifecycle management, it is therefore helpful to establish a robust change control system that evaluates CMC changes and manages them correctly from a regulatory standpoint.
After market entry, generics are subject to the same drug safety obligations as reference products. These include a functioning pharmacovigilance system, the assessment of adverse reaction reports, and, if applicable, periodic safety update reports, depending on the status of the product and national requirements. Especially with high prescription volumes, even rare signals can become visible, which is why data quality and timely signal evaluation are decisive in routine practice.
Relevance for Reimbursement, Healthcare Provision, and Tenders
Generics play a major role in cost containment within healthcare systems and are closely linked to reimbursement and pricing rules. In Germany, fixed-price groups, discount contracts, and substitution rules influence market success. For companies, the ability to deliver and quality assurance are also central success factors, as tenders and discount contracts can significantly shift market shares.
In the reality of healthcare provision, special requirements arise for active substances with a narrow therapeutic index, for complex application systems, or when switches between manufacturers occur. In these cases, the package leaflet, educational materials, and pharmacovigilance processes must be consistent to avoid medication errors and supply risks.
From a regulatory perspective, it should also be considered that differences in excipients or pharmaceutical preparation can become relevant for certain patient groups, such as those with allergies, swallowing disorders, or in pediatrics. Even if this does not necessarily lead to a different authorization pathway, a clear risk assessment in the product lifecycle is advisable.
FAQ
Is a generic always identical to the original?
The active substance, strength, and dosage form are comparable, but excipients, manufacturing processes, or packaging design may differ. The decisive factor is that quality and bioequivalence are proven, and thus therapeutic comparability is expected.
Why does a generic usually not require large efficacy studies?
The clinical efficacy of the active substance has already been proven. The generic application must primarily demonstrate that the exposure in the body corresponds to that of the reference product; bioequivalence data are used for this purpose.
When is additional data beyond bioequivalence necessary?
For complex dosage forms, locally acting products, or specific safety aspects, authorities may request additional in vitro or clinical data to demonstrate adequate comparability.
Regulatory References (Selection)
- Directive 2001/83/EC (Community code relating to medicinal products for human use), Art. 10 (abbreviated applications)
- Regulation (EC) No 726/2004 (centralized procedure, EMA)
- EMA Guideline on the investigation of bioequivalence (current version)