Author: Tobias Schüning, Consultant, Market Access
Aut‑idem Meets Biologics: Mandatory Substitution as a Game Changer in Germany (Medicines Directive (AM‑RL) §40c)
Introduction
Germany is introducing mandatory substitution for biological medicinal products at the pharmacy level, a major regulatory shift that de facto applies an aut-idem logic to biologics with available biosimilars. The new ruling might lead to market share mechanics as previously known from generic drugs.
Regulatory Background
From 01 April 2026, pharmacies must substitute prescribed biologics with a lower‑cost biological medicine (biosimilars), if they match the original product in strength, pack size, dosage form, container requirements, indication, and routes of administration. Thereby, newly introduced §40c AM‑RL extends substitution beyond parenteral products as previously defined in §40b AM‑RL to all ready‑to‑use biologics listed in Annex VIIa of the AM-RL, significantly widening the prior substitution scope. The new pharmacy level ruling thereby also extends previous §40a AM-RL, which already demands physicians to consider a switch to a more economic biosimilar option if available – in the course of a running biologic therapy or at therapy initiation. The selection of substitution partners in context of §40c is strictly defined: rebate contract products first, otherwise the most economical option under the framework agreement. Prescribers may exclude substitution only with explicit medical justification.
Implications
The reform introduces a system‑driven competitive dynamic that will put more pressure on biosimilar driven competition and thereby accelerates the risk of market share loss for originator products once exclusivity expires. Pharmacy‑level substitution increases payer‑driven switching and amplifies price pressure, making rebate agreements a critical factor for maintaining market share. As dispensing decisions become increasingly governed by economic rules, lower cost biosimilars can potentially gain larger market shares, while originator products and also biosimilar offerings that cannot hold up with further price reductions or existing rebate agreements are exposed to faster and more pronounced competitive pressure.
What Does This Mean for Pharma?
The real-life impact of the new ruling and potentially resulting market dynamics in biosimilar-affected indications must be followed with caution. Companies must prepare for the potential of accelerated erosion, increased substitution frequency, and heightened pricing competition, which could also impact price developments of affected reference price groups. Effective contracting strategies, close monitoring of price movements, and robust forecasting of payer and substitution behaviour become essential to defend or grow market position in a more economically driven environment.
Our Value Proposition at Kintiga
At Kintiga we support pharma and biotech companies with proven tech-enabled solutions, like our proprietary MAIS database, and our deep local AMNOG expertise. We help our clients navigating the AMNOG landscape with tailored strategies and market access expertise that anticipates payer expectations and dynamic market changes.
Sources:
- Austauschbarkeit von Biologika in Apotheken: Regelungen des G-BA treten am 1. April 2026 in Kraft – Gemeinsamer Bundesausschuss
- Biologika und Biosimilars: Austauschbarkeit von biotechnologisch hergestellten Arzneimitteln – Gemeinsamer Bundesausschuss
- Austauschbarkeit von verordneten Biologika: G-BA definiert die Voraussetzungen – Gemeinsamer Bundesausschuss
- Amtliche Veröffentlichungen – Bundesanzeiger: BAnz AT 27.02.2026 B3
