Companion Diagnostics (CDx): What’s Driving the Increase in Pharma Demand?
What Are Companion Diagnostics?
A companion diagnostic (CDx) is a medical device, often an in vitro diagnostic (IVD), which provides essential information for the safe and effective use of a corresponding pharmaceutical drug or biological product. Companion diagnostics match patients to targeted therapies by identifying specific biological markers, predicting who will respond well to treatment as well as those who might be at risk of serious adverse side effects.
Precision Medicine – Moving beyond “one-size-fits-all” medicine
At its core, a companion diagnostic enables a simple yet powerful shift: treating the right patient, with the right drug, at the right time. By identifying patients with the relevant biomarker, genetic profile, or disease subtype, CDx allows therapies to be targeted more precisely, improving both efficacy and safety.
This is precision medicine. And for the pharma industry, it isn’t just a scientific improvement, it’s a strategic advantage.
The Rise of Companion Diagnostics
We’ve seen a noticeable shift recently. Companion diagnostics (CDx) are no longer a future consideration for pharma teams. They’re becoming an immediate priority.
Over the past 6–12 months, we’ve had a growing number of conversations with pharma partners looking to actively integrate diagnostics into their development programmes, as a core part of their strategy rather than an add-on.
These aren’t early exploratory discussions, but increasingly commercially driven, time-sensitive enquiries focused on how to integrate diagnostics into drug development and lifecycle strategy.
So what’s driving this shift?
- Improving clinical trial success rates
One of the biggest drivers behind CDx adoption is its impact on clinical development. In an environment where clinical trials are increasingly expensive and high-risk, CDx provides a clear route to de-risking development programmes.
By selecting patients who are more likely to respond, trials become more predictable and efficient. Smaller, more focused patient cohorts can be used, response rates improve, and the risk of failed endpoints is reduced.
- Regulatory expectations are evolving
Regulators are placing increasing emphasis on targeted therapies, particularly in areas such as oncology and precision medicine. In many cases, a drug is now expected to be approved alongside a diagnostic that defines the eligible patient population.
This creates a strong incentive for pharma to engage with diagnostic partners earlier in development, to ensure alignment between the therapeutic and diagnostic pathways
- Commercial and reimbursement advantages
Beyond development, CDx plays a critical role in how therapies are positioned in the market.
Companion diagnostics help to clearly demonstrate clinical value and differentiation, which could support premium pricing strategies and reduce spend on non-responding patients. In short, CDx strengthens the case for both adoption and reimbursement.
- Real-world monitoring and treatment optimisation
The role of CDx doesn’t stop at patient selection. Diagnostics are increasingly being used to monitor treatment response over time, detect resistance or disease progression, and therefore inform treatment switching or escalation. This creates a more dynamic, data-driven treatment pathway, improving long-term patient outcomes.
Why pharma is actively seeking diagnostic partners
The shift we’re seeing isn’t just about recognising the value of CDx — it’s about capability gaps. Developing a companion diagnostic requires working to a stringent QMS, often relying on specialist capabilities and equipment that aren’t usually associated with a pharmaceutical company, including:
- biomarker identification and validation
- assay development and optimisation
- regulatory alignment
- clinical validation
- scalable manufacturing
Many pharma organisations are choosing to partner with specialist diagnostic developers to accelerate this process and reduce complexity.
From concept to commercial reality
At Medtechtomarket, we work with partners across the full CDx pathway — from early biomarker feasibility through to validated, manufacturable diagnostic products.
What’s changed recently is the urgency and clarity of the conversations we’re having. Pharma is no longer asking if they should integrate diagnostics, rather “How quickly can we make this part of our programme?”
Companion diagnostics are no longer a “nice to have” alongside drug development. They are becoming a core component of modern therapeutic strategy, shaping how drugs are developed, approved, and adopted. And if the volume of enquiries we’re seeing is anything to go by, this shift is only accelerating.
Supporting Your Diagnostic Development
If you’re exploring how a companion diagnostic could support your programme – whether at early biomarker stage or alongside an existing asset – it’s worth having that conversation early. If you’d like to discuss your programme or sense-check your approach, feel free to get in touch.