The adult epilepsy market across the seven major markets (7MM: the US, France, Germany, Italy, Spain, the UK, and Japan) is poised to grow at a compound annual growth rate (CAGR) of 4.4% from $11.4bn in 2025 to $17.8bn in 2035, according to GlobalData’s recently published report, ‘Epilepsy (Adults): Disease Analysis Report and Forecast‘. This growth will be driven by an increase in diagnosed prevalent cases as well as the introduction of 12 late-stage pipeline products: relutrigine, vormatrigine, Staccato alprazolam, bexicaserin, clemizole hydrochloride, RAP-219, opakalim, carisbamate, zorevunersen sodium, ETX101, and Rezanecel.
For the majority of patients with focal or generalised epilepsies, pharmacotherapy with anti-seizure medications (ASMs) remains the cornerstone of therapeutic management. Many ASMs have been on the market for a long time and are available in cheap generic forms. For generalised epilepsies, valproate is the broadest-spectrum first-line agent, with lamotrigine, levetiracetam, and ethosuximide fulfilling established adjunctive roles depending on seizure type. In focal epilepsies, the first-line agents also include lamotrigine and levetiracetam, with alternative agents such as carbamazepine being introduced should these options fail.
Should the initial therapeutic cocktail not control seizures, other second- and third-line therapies such as oxcarbazepine, zonisamide, or valproate are considered. Pregabalin and gabapentin may also be used for adults with drug-resistant focal seizures, with or without secondary generalisation. Additionally, in both focal and generalised seizures, benzodiazepines are also used as fast-acting preventative or ‘rescue’ medications to stop acute, prolonged, or cluster seizures, and treat status epilepticus. The epilepsy market has recently seen meaningful advances with so-called third-generation ASMs. The third-generation agents approved over the past decade for focal epilepsy include lacosamide, eslicarbazepine, perampanel, brivaracetam, and cenobamate. These have fueled growth in the past decade, yet this growth has begun to stagnate, given the growing maturity of these products on the market. As a result, there is space for novel agents to enter.
Epilepsy syndromes such as Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS) require more nuanced approaches to treatment, due to their distinct aetiologies. DS represents one of the most medically severe rare epilepsy indications, characterised by its onset in infancy, loss of function of the SCN1A gene that underpins its pathophysiology, and its profound resistance to conventional ASMs. Established ASMs, sodium channel blockers such as carbamazepine, lamotrigine, phenytoin, and oxcarbazepine, are all contraindicated in DS, as they can paradoxically worsen seizure burden. Therefore, in DS, the treatment foundation rests on valproate, typically with clobazam as a second agent, forming the backbone of management in most regions. There have been syndrome-specific agents introduced over the past several years, which has substantially enriched the therapeutic toolkit: fenfluramine, stiripentol, and cannabidiol are all approved add-on therapies for seizures in DS. LGS is another refractory epilepsy syndrome, characterised by its heterogeneous aetiology, multiple co-occurring seizure types, and invariable requirement for polypharmacy to manage seizures. The backbone of LGS management has traditionally comprised valproate, lamotrigine, clobazam, topiramate, and rufinamide in combination regimens.
Despite a crowded landscape, there are significant clinical unmet needs in epilepsy treatment. Key opinion leaders (KOLs) have bemoaned the lack of effective therapies for epilepsy, citing that seizure freedom rates remain stable, despite the wide array of ASMs currently available on the market. KOLs have noted that currently marketed therapies focus on synaptic mechanisms and look to either decrease excitation or increase inhibition. These treatments increase the likelihood of adverse effects, due to the ubiquity of receptors and synapses throughout the brain. They are more symptomatic in their approach and do not address the underlying pathologies that produce seizures. There are several pipeline therapies that also operate on synaptic mechanisms, and although demonstrating potential, are likely to encounter similar issues as currently marketed therapies. This has been recognised by pharmaceutical companies, and disease-modifying therapies (DMTs) are beginning to emerge in the pipeline: of the 12 late-stage pipeline agents, three of them—Stoke Therapeutics’ zorevunersen sodium, Encoded Therapeutics’ ETX-101, and UCB’s rezanecel—are being trialed for their disease-modifying potential in epilepsy. This signals a shift in the treatment paradigm towards therapies targeting the underlying pathophysiology of the condition. GlobalData forecasts that the late-stage pipeline products could drive combined sales of approximately $5.4bn by 2035 in the 7MM, with DMTs expected to comprise roughly a quarter of this figure. GlobalData also anticipates that the most promising pipeline product will be Praxis Precision Medicine’s vormatrigine, which is currently being trialed in focal and generalized epilepsy. It is expected that despite the emergence of DMTs, access to these therapies is likely to be limited, given their anticipated high cost. Therefore, symptomatic treatments will remain first-line, with novel entrants an attractive option. Vormatrigine in particular has the potential to see strong uptake due to its efficacy in clinical trials and its distinct mechanism of action amongst sodium channel blockers, leveraging more selective sodium channel modulation than traditional sodium channel blocking drugs.
Although the epilepsy market is dominated by cheap generics that will act as a major barrier to growth, late-stage pipeline products have potential to generate significant growth in the epilepsy market. This, coupled with the increase in diagnosed prevalent cases, will act as the main drivers of growth across the 7MM.
