GLP-1, Cell/Gene Therapy, and ADCs: How Modality Shifts Reshape CDMO Demand

Introduction

The CDMO industry is being reshaped by three simultaneous modality shifts that are redirecting capital expenditure, driving M&A activity, and creating new winners and losers across the manufacturing landscape. Traditional small molecule and standard monoclonal antibody manufacturing, while still the largest revenue pools, are growing slowly and facing pricing pressure. The growth and strategic value are concentrating in GLP-1 peptides, cell and gene therapy, and antibody-drug conjugates, each of which requires specialized capabilities that most legacy CDMOs lack.

The GLP-1 revolution created the most acute manufacturing capacity shortage in pharma history. Semaglutide (Novo Nordisk) and tirzepatide (Eli Lilly) are complex peptides that require solid-phase peptide synthesis (SPPS), a manufacturing process that is capacity-intensive and slow to scale. As GLP-1 prescriptions surged from diabetes into the far larger obesity market, both companies found their manufacturing capacity unable to meet demand.

Novo Nordisk's response was direct: its parent company, Novo Holdings, acquired Catalent for $16.5 billion in 2024, securing three fill-finish manufacturing facilities and converting them to semaglutide production. This transaction redefined the CDMO landscape in several ways.

The GLP-1 manufacturing bottleneck extends beyond fill-finish. Peptide API synthesis requires specialized equipment (peptide synthesizers, HPLC purification systems) that has 18-24 month lead times. Device assembly for auto-injector pens adds another capacity constraint. The entire GLP-1 supply chain, from API synthesis through formulation, fill-finish, device assembly, and packaging, is operating near full utilization, creating opportunities for CDMOs that can offer capacity at any point in the chain.

Cell and gene therapy manufacturing is fundamentally different from traditional pharmaceutical manufacturing, and this difference creates both enormous challenges and enormous opportunities for CDMOs.

Autologous vs. Allogeneic Manufacturing

Autologous cell therapies (like CAR-T) use the patient's own cells, meaning each manufacturing batch serves exactly one patient. The process involves collecting the patient's cells, shipping them to a manufacturing facility, genetically modifying them, expanding them, quality-testing them, and shipping them back. This one-patient-per-batch model is inherently unscalable and expensive ($300K-$500K manufacturing cost per patient). Allogeneic therapies use cells from a healthy donor to create an off-the-shelf product that can treat many patients from a single manufacturing batch. Allogeneic manufacturing is more similar to traditional biologics (batch-based, scalable) but is still in early clinical development for most indications.

The CGT CDMO market was approximately $1.6 billion in 2023 and is projected to reach $10.3 billion by 2033, representing one of the fastest-growing segments in all of life sciences outsourcing. This growth is driven by two factors. First, CGT companies are overwhelmingly small biotech firms that lack internal manufacturing capabilities and structurally depend on CDMOs. Second, CGT manufacturing requires specialized viral vector production (AAV, lentivirus), cell processing, and quality testing capabilities that take years to build internally.

The CGT CDMO landscape is bifurcated. For viral vector production (the core input for gene therapies), capacity has expanded significantly since the initial shortage of 2019-2021, and some CDMOs now face underutilization as clinical programs have progressed more slowly than expected. For autologous cell therapy manufacturing (CAR-T), the vein-to-vein logistics and one-patient-per-batch economics continue to challenge both CDMOs and sponsors.

Antibody-drug conjugates combine a monoclonal antibody with a cytotoxic payload through a chemical linker. Manufacturing ADCs requires three distinct capabilities: antibody production (standard biologics manufacturing), payload synthesis (highly potent API handling requiring specialized containment), and conjugation chemistry (linking the payload to the antibody with precise drug-to-antibody ratios).

The conjugation step is the bottleneck. Handling cytotoxic payloads requires containment facilities (nanogram-level occupational exposure limits), specialized equipment, and trained personnel. Few CDMOs have validated ADC conjugation capabilities, and building new facilities takes 2-3 years. As the ADC pipeline has expanded from roughly 100 clinical programs in 2020 to over 300 in 2025, demand for conjugation capacity has outstripped supply.

The next article covers the BIOSECURE Act and reshoring of pharma manufacturing, which is accelerating the shift of CDMO demand from Chinese providers to Western alternatives.