How Overall Equipment Effectiveness Predicts Pre-Filled Syringe Capacity at a CDMO

Overall Equipment Effectiveness (OEE) is the most reliable indicator of a Contract Development and Manufacturing Organisation’s (CDMO) true available capacity for pre-filled syringe fill-finish. It combines three measurable factors, Availability, Performance and Quality, to reveal how much productive manufacturing time a filling line can realistically deliver. Sponsors evaluating a CDMO for large-scale commercial sterile injectable production must look beyond stated theoretical throughput and examine how these three components interact with batch scheduling density to determine whether genuine supply security exists.

Why Theoretical Throughput Figures Do Not Tell the Full Story

A filling line rated at hundreds of syringes per minute sounds substantial. But a sponsor preparing to launch a commercial product needs to understand how consistently that line operates at its rated speed, for how long per campaign and what proportion of filled units pass final inspection without rework. Theoretical capacity figures do not answer those questions.

The sterile fill-finish environment introduces complexity that is largely absent from general-purpose manufacturing. Aseptic processing controls, Cleaning in Place and Sterilisation in Place cycles, environmental monitoring hold periods, Aseptic Process Simulation scheduling and multi-product campaign sequencing all reduce the time a filling line spends in productive operation. A sponsor who relies solely on a CDMO’s headline throughput number risks discovering the gap between nominal and actual capacity only when it begins to affect supply continuity.

OEE transforms that gap into a measurable, auditable figure. The United States Food and Drug Administration’s guidance on sterile drug products produced by aseptic processing makes clear that the quality and integrity of an aseptic manufacturing process depends on the combined effectiveness of equipment, environment and operational controls, all of which OEE is designed to quantify.

The Three Components of OEE Applied to Sterile Fill-Finish

Overall Equipment Effectiveness is calculated by multiplying three ratios: Availability, Performance and Quality. Each carries specific meaning in a pre-filled syringe manufacturing context.

Availability: How Much Planned Time Is the Line Actually Running?

Availability measures the proportion of planned production time during which a filling line is operational and productive. In sterile injectable manufacturing, the losses that reduce availability are significant and, in most cases, non-negotiable.

Changeover and cleaning. Every product transition on a shared filling line requires full line clearance, decontamination and re-qualification before the next campaign begins. Where controlled substances are involved, the scope and documentation of these steps increases considerably. The 2022 revision of European Union Good Manufacturing Practice Annex 1 sets detailed requirements for contamination control strategies in sterile manufacturing environments, directly influencing the duration and documentation burden of changeover activities.

Aseptic Process Simulation runs. Regulatory requirements mandate that aseptic filling lines complete media fills at defined intervals to validate the integrity of the aseptic process. Each simulation run occupies planned line time, and the frequency increases with product turnover across the facility.

Preventive maintenance and equipment qualification. High-speed filling lines require scheduled calibration, component replacement and engineering maintenance. Any change to a critical system component triggers requalification activity before the line returns to commercial production.

A sponsor should request a CDMO’s planned maintenance schedule and confirm how maintenance windows are distributed across the calendar year. A facility that plans and documents these events systematically demonstrates the operational maturity required for reliable commercial supply.

Performance: How Close Does Actual Output Come to the Maximum?

Performance measures the ratio of actual output rate to theoretical maximum rate during periods when the line is running. Even with a line in operation, speed losses occur through micro-stoppages, component feeding irregularities and fill volume adjustments during routine in-process checks.

For pre-filled syringe production, format compatibility is directly relevant here. A filling line validated for specific syringe formats has defined and validated speed envelopes for each. A sponsor must understand whether their target container format is covered and what the validated fill speed is for that format, not simply the line’s peak rated capability at its fastest configuration.

Consistency of performance across campaigns matters as much as the headline figure. Requesting historical batch records or equivalent campaign summary data allows a sponsor to assess whether line speed targets are routinely achieved or whether performance degrades over the course of longer campaigns.

Quality: What Proportion of Filled Units Pass Inspection and Release?

The Quality component of OEE accounts for the proportion of filled units that pass inspection and release without rejection or rework. In pre-filled syringe manufacturing, 100% visual inspection is standard practice. Automated inspection systems identify particulate contamination, fill volume deviations, container defects and closure integrity failures at production speed.

A CDMO that has invested in high-throughput automated inspection in-line reduces batch-level quality risk and limits the exposure to human variability at the inspection stage. The rejection rate, and the distribution of rejection causes across failure modes, should be a standard item on the agenda of any capability audit. A pattern of consistent, low rejection rates across campaigns indicates a mature and well-controlled process; unpredictable rejection rates warrant further investigation.

Batch Scheduling Risk: The Most Commonly Overlooked Variable

Even a facility with excellent Overall Equipment Effectiveness can present a supply risk if its schedule is already heavily committed. Batch scheduling density, meaning the proportion of available manufacturing slots already allocated to existing clients, is one of the most consistently underweighted factors in CDMO selection for commercial programmes.

Sponsors should raise the following during due diligence:

• Lead time from order to batch initiation. A CDMO operating near full capacity will show extended lead times. A lead time substantially longer than the facility’s own published norm warrants direct investigation.
• Campaign structure. Determine whether your product will be produced in dedicated campaigns or interleaved with other products on the same line. Interleaving increases changeover frequency, adds scheduling complexity and can shorten the effective production window per batch.
• Contingency and redundancy. If the primary filling line requires an unplanned outage, does the facility have a second line capable of absorbing the batch without displacing another client’s committed campaign?
• Schedule transparency. Does the CDMO operate a manufacturing execution system or equivalent scheduling tool that provides clients with meaningful visibility into their batch status and confirmed start date?

A CDMO that answers these questions with documented evidence, rather than general assurances, has the governance infrastructure to support a commercial product reliably through launch and into sustained supply.

What to Request During a CDMO Capacity Audit

When conducting structured due diligence on a CDMO’s capacity for commercial pre-filled syringe fill-finish, the following documentation should form the basis of your assessment:

Requesting this documentation is standard practice for commercial due diligence. A CDMO that declines to provide it at an appropriate stage of engagement is communicating something meaningful about its operational transparency. The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use Q10 Pharmaceutical Quality System guideline
sets out the quality management principles that underpin this level of documentation and process control.

Adragos Pharma: Infrastructure Designed for High-Volume Pre-Filled Syringe Supply

At Adragos Pharma’s facility in Maisons-Alfort, France, the pre-filled syringe manufacturing infrastructure is designed specifically for large-scale commercial production. The site operates two dedicated filling lines, both equipped with Restricted Access Barrier System (RABS) technology to maintain aseptic conditions throughout high-speed production. Filling capacity reaches up to 540 syringes per minute, supporting an annual output of up to 150 million units.

Downstream of filling, two fully automated Seidenader inspection lines perform 100% automated visual inspection at speeds of up to 600 syringes per minute. Five packaging lines, including a dedicated plastic-free line for Eris™ syringe formats, handle kit assembly across a range of configurations from two-syringe packs through to 76-syringe formats, including Bag-in-Box options.

The facility holds European Union Good Manufacturing Practice certification and has been assessed by 12 international health authorities. It is engineered for United States Food and Drug Administration readiness and is designed to support sponsors pursuing global commercial supply from a single, well-established manufacturing site.

With over 77 years of experience in sterile drug manufacturing, Maisons-Alfort brings the process documentation depth, engineering standards and regulatory track record that sponsors need to evaluate when selecting a CDMO partner for a commercial-stage sterile injectable programme.

Sponsors requiring clinical trial material manufacturing prior to commercial scale-up can also access Adragos Pharma’s facility in Jura, Switzerland, which specialises in aseptic fill-finish for liquid and lyophilised vials, supporting the transition from early-phase development through to commercial readiness.

Key Questions to Ask Any CDMO Before Committing a Commercial Pre-Filled Syringe Programme

• What is the confirmed annual capacity available for our target format, after accounting for existing client commitments?
• How many filling lines are available for our product, and are any of those lines dedicated to a single product or client?
• What is the average lead time from order to batch initiation for a campaign of our projected annual volume?
• How are Aseptic Process Simulation runs scheduled, and what proportion of annual line time do they account for?
• What redundancy does the facility provide if the primary filling line requires an unplanned outage mid-campaign?
• Can you provide line utilisation data for the past 12 to 24 months, including a breakdown of planned and unplanned downtime?

A CDMO that answers these questions with verifiable data, rather than general statements of capability, has the operational rigour to be considered a credible partner for commercial supply at scale.