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For millions of people with rare diseases, life often narrows to hospital visits, uncertainty, and the long wait for answers. Even when a diagnosis comes, it rarely brings relief, as over 90 per cent of the 7,000 known rare diseases have no approved treatment.
Yet what was once considered an intractable corner of medicine is fast becoming a proving ground for the future of healthcare. Innovations in genetics, RNA therapies, and gene editing are shifting the boundaries of what’s possible. For long-term investors, one insight is becoming clear: companies solving rare diseases today are building the foundations of tomorrow’s global health solutions.
In the Positive Change portfolio, two companies – Alnylam and Vertex – exemplify this idea. Their breakthroughs in rare disease are already rippling outward, reshaping what’s possible for far more common conditions. Today, both are translating scientific promise into real-world impact – launching new treatments, expanding into broader markets, and showing what the future of medicine could look like. These are not just success stories in science, but proof points for how long-term impact and attractive returns can go hand in hand.
Why rare diseases are a catalyst for global progress
Each rare disease may affect only a few thousand people, but collectively, they impact hundreds of millions worldwide. And because traditional drug development models often bypass these conditions, the scientific challenges are steep. That pressure has led to unconventional thinking and the birth of new platforms.
These platforms aren’t one-off solutions. They’re reusable engines of innovation. The insights, tools, and regulatory know-how developed for rare diseases can be – and increasingly are – adapted to more widespread illnesses.
This is the flywheel in motion: solving the problems by tackling rare diseases first creates leverage for solving everything that follows.
Alnylam: muting the source of disease
When Alnylam Pharmaceuticals launched, the concept of switching off harmful genes felt like science fiction. Today, its RNA interference (RNAi) platform has turned that fiction into a scalable reality by effectively “muting” faulty instructions at the genetic level before they can do harm.
Since joining the Positive Change portfolio in 2017, full-year revenues have grown from around $90mn to $1.6bn. But more telling is the platform’s adaptability. Once Alnylam’s delivery mechanism works for one condition, it can be repurposed for many.
Having started with treatments for rare conditions such as hATTR amyloidosis and acute hepatic porphyria – affecting the heart, liver, kidneys, and nervous system – Alnylam has improved the quality of life for patients who previously had limited or no options. For many, that means fewer symptoms, less time in hospital, and more time living fully.
Alnylam is now moving into more prevalent conditions – like hypertension – where its investigational therapy could allow control with just two injections per year. That’s rare-to-universal in action: deep science refined on the margins, poised to benefit tens of millions.
Vertex: expanding the impact horizon
Vertex Pharmaceuticals is a newer addition to the Positive Change portfolio, added in late 2024. The company initially gained recognition for its groundbreaking work in cystic fibrosis (CF), transforming it from a fatal childhood illness into a manageable adult condition. For patients, that means improved lung function, fewer hospital visits, and longer, healthier lives.
Since launching its first CF treatment in 2012, Vertex has not only delivered medical impact but also outstanding shareholder value – revenues have grown from $1.5bn to over $11bn in 2024. Vertex’s success has been rooted in its ability to expand from treating hepatitis C to cystic fibrosis, and now to an even wider range of conditions.
The company’s platform spans gene editing, small molecules, and cell therapy – tools now being applied to broader health challenges, including pain management. In 2025, Vertex launched an FDA-approved, non-opioid therapy for acute pain. This treatment addresses a potential market of hundreds of millions, while offering an alternative in a space still reeling from the opioid addiction crisis.
At Positive Change, we take a long-term approach to investing in healthcare – looking for companies whose innovations not only improve lives but also hold the potential to deliver sustained financial returns. As Vertex moves into new treatment areas, we believe its continued ability to challenge the status quo may lead to significant societal benefit and strong long-term value for investors.
Why it matters for health returns
Investing in rare disease innovation isn’t concessionary or unprofitable. It’s long-term investing with a focus on developing the innovation engines at companies that have the ability to transform healthcare. Each therapeutic advance adds not just a treatment, but a layer of knowledge – data, delivery systems, regulatory frameworks – that makes the next breakthrough faster and more cost-effective.
This compounding edge – the ability to do more and better with each success – is why companies like Alnylam and Vertex are so powerful. They don’t just chase individual wins; they build momentum.
That’s exactly what Positive Change looks for: mission-led businesses with platforms that scale both impact and performance over time. It’s not the easiest path, but it may be the most transformative.
From rare to universal: a blueprint for progress
The convergence of science, purpose, and long-term capital is enabling a new kind of healthcare transformation – one that starts at the margins and scales to the mainstream.
By backing pioneers in rare disease, we’re not only helping the people most often left behind, but we’re accelerating the breakthroughs that will benefit everyone.
You can invest in companies driving positive change and tackling challenges that span the biggest environmental and social issues. Find out more about Positive Change.
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