Building an evidence-based market sizing strategy for an autoimmune condition
CF was commissioned by a global pharmaceutical manufacturer to deliver an evidence-based market sizing report for a targeted therapy in a chronic multisystem autoimmune condition. With global market estimates proving inadequate for the UK context, where advanced therapies are reserved for refractory disease, CF conducted a rigorous, UK-specific analysis combining epidemiological modelling, HES acute care data and SCMD prescribing analysis across 66 NHS Trusts. The result was a defensible, health system-anchored estimate of the biologic-eligible population in England, giving the client a robust foundation for their HTA submission and pre-launch market access strategy.
What was the challenge?
A global pharmaceutical manufacturer was preparing for the UK launch of a targeted therapy for a complex auto-immune condition. While global and European market estimates existed, these were largely unsuitable for the UK context, where NHS treatment pathways differ significantly, with advanced biologic therapies reserved for patients with refractory, moderate-to-severe disease.
This meant that standard global extrapolations risked substantially overstating the true addressable population in England, undermining the credibility of the company’s market access strategy and HTA submission. Without a robust, UK-specific estimate of the biologic-eligible patient population, one grounded in real healthcare system activity rather than contested global figures, the client lacked the evidence base needed to build a defensible business case, allocate resources appropriately, or engage confidently with payers ahead of launch.
What did we do?
CF delivered a comprehensive, UK-specific market sizing report built on three interlocking analytical workstreams, triangulating evidence from epidemiology, healthcare activity data and real-world prescribing to produce a single, converged estimate of the biologic-eligible population in England.
By converging these three approaches, CF produced a robust treatment anchor that grounded the final market size estimate firmly in NHS activity rather than global extrapolation.
Estimating the addressable population through triangulation
Targeted literature reviews
- UK/England prevalence
- Severity split (mild/moderate/severe)
- Biologics eligible
HES APC, OP, ECDS (ICD-10 M32, SNOMED codes)
- Active cohort with codes
- Organ involvement codes
- High utilisers (e.g., >3 inpatient spells YoY)
Secondary Care Medicines Database (DDD from 66 Trusts, 61% coverage of England)
- Product X pts (estimated per DDD)
- Product Y pts (estimated per DDD)
from epidemiological data
from HES activity data
from SCMD medicine volumes
Step-by-step estimation of biologics-eligible patients in England
| England Population | ONS 2025 | |
| Total England resident population estimate from the Office for National Statistics mid-year 2025 projection. | ||
| Prevalence | Published sources, CF analysis, epi model | |
| Estimated prevalence applied to England population using CF epidemiological model, calibrated to latest published sources (2024). | ||
| Biologics eligible (adjusted) | Adjusted for eligibility based on literature/clinical sources | |
| Eligibility-adjusted estimate accounting for contraindications, comorbidities and clinical practice patterns that reduce the biologics-eligible proportion. | ||
| Current Product X usage | Estimated treated population (NHSE Trusts) | |
| Product X patient numbers extrapolated from NHSE Trust-level prescribing data to national England coverage using SCMD trust coverage ratio. | ||
| Current Product Y usage | Estimated treated population (NHSE Trusts) | |
| Product Y patient numbers derived from NHSE Trust-level data, extrapolated to national level. | ||
| Estimated patients on biologics | All patients treated with Products X+Y | |
| Combined addressable patient population for Product X and Product Y, representing the total estimated biologics market in England. | ||
What was the impact?
CF’s analysis gave the manufacturer a defensible, NHS-grounded view of the true addressable market in England, replacing contested global extrapolations with evidence drawn directly from healthcare system activity.
The work delivered across three key areas:
- A credible market size estimate: An evidence-based, UK-specific estimate of the biologic-eligible population, providing a defensible starting point for payer engagement and HTA submission that could withstand scrutiny from commissioners and regulators.
- A replicable analytical framework: CF’s methodology was designed to be updateable and scalable, giving the client a living tool for ongoing market shaping, launch forecasting and pre-launch strategic planning as the therapy moves closer to market.
- A stronger business case: The analysis directly informed the company’s resource allocation decisions ahead of anticipated regulatory and reimbursement milestones, ensuring internal investment was anchored in realistic, England-specific patient numbers.
