Author: Dr Matt Williams

There is strong evidence that Tumour Treating Fields (TTF) improve survival rates in GBM patients. This technology is available through the health services of several countries, including Germany, Austria, Sweden, France, Switzerland, the USA, Japan, and Israel. In Italy and Spain, it is accessible in certain regions. Published appraisals exist from Canada, France, Sweden, and Switzerland. The trade name for TTF is Optune®.

In the UK, TTF is available to private patients, but NICE has not yet appraised it. This has led to significant barriers, including high costs for self-funding patients, unequal access depending on private insurers, and the UK lagging behind other countries in offering this treatment. Cost appears to be a primary barrier; however, informal discussions with the technology owner indicate awareness of NICE’s cost thresholds. Similar conversations have taken place with other regulators in Europe and Canada.

We believe it is both appropriate and necessary to request a NICE appraisal of TTF for UK use. This would demonstrate that the new Government is taking decisive action on one of the UK’s most pressing cancer challenges. Beyond making TTF available, such a move would signal the UK’s commitment to innovative treatments and increase the likelihood of participation in future clinical trials.

Evidence

The key trial, EF-14, compared standard chemo-radiotherapy to chemo-radiotherapy plus TTF in adults with newly diagnosed GBM. Results showed:

• Median overall survival (OS) increased from 16 months to 20.9 months.
• Two-year survival improved from 31% to 43%.
• Five-year survival rose from 5% to 13%.
• Longer wear time was associated with better survival outcomes.
• The only notable side effect was skin irritation.

Additionally, the TIGER study from Germany provided real-world data on 710 GBM patients offered TTF. Findings showed a 60% uptake rate, with survival outcomes comparable to EF-14 (median OS: 19.6 months; two-year OS: 42%). Side effects remained limited to skin irritation.

Funding, Access, and Trials

TTF is currently available in multiple countries. In the UK, it is routinely covered by two of the four major insurers. It is also available on a self-pay basis, though costs (£15,000-£20,000 per month) make it inaccessible for most patients. Previously, UK patients could access TTF through the TRIDENT trial, which was limited to just 30 UK participants out of 950 globally. With recruitment now complete, UK participation in future trials remains limited due to the lack of approval.

Because TTF is not formally approved, the UK has a restricted role in upcoming trials. For example, the EF-41 trial, which evaluates chemo-radiotherapy + TTF + Pembrolizumab, will have approximately five UK sites and recruit only 30-50 patients.

NICE Summary

In August 2024, NICE confirmed it would not prioritise TTF for review, citing:

• A limited evidence base.
• High costs.
• Ongoing trials.
• Development of a new joint NHSE-NICE Medical Technology Pathway.

However, most studies cited by NICE were small Phase 1-2 trials. The TRIDENT trial, while significant, does not provide evidence for TTF’s effectiveness since all patients in the study had access to it. Waiting for additional studies may not substantially change the outcome of any future appraisal.

Funding and Access

TTF is now recommended for newly diagnosed GBM treatment in the USA (NCCN guidelines), and Canadian guidelines recommend public funding.

In the UK:

• Novocure provides TTF through private partnerships.
• It is covered by BUPA and AVIVA, as well as smaller insurers like CIGNA and Allianz.
• AXA-PPP and Vitality do not currently cover TTF, though patient-led appeals are ongoing.

The UK has participated in one major TTF-based GBM trial (TRIDENT), a large Phase 3 study assessing TTF’s use alongside chemotherapy. Of 950 participants, only ~20 were from the UK. Results are expected in three years. Future large-scale trials, such as EF-41, are planned but have limited UK involvement due to the lack of national approval.

NICE Guidance and Discussions

NICE published its brain tumour guidance (NG99) on July 11, 2018, and updated it in 2021 concerning stereotactic radiotherapy. At the time of initial publication, only interim EF-14 data was available, though full results were released in 2017. NG99 currently recommends against TTF use.

Novocure engaged with NICE in 2024, but NICE declined to appraise Optune, citing limited evidence and high costs. Their response included a list of pending studies expected to conclude within 18-24 months:

Pending Studies:

• TIGER Study (Germany) – Prospective non-interventional study, pending publication.
• RCT (n=950) – Testing Optune’s early introduction in treatment, results expected in 2026.
• Phase 2 (2025) – Evaluating Optune with pembrolizumab and temozolomide.
• Phase 2 (2025) – Niraparib + TTF for recurrent GBM.
• Phase 2 (Dec 2024) – Radiosurgery + TTF for recurrent GBM.
• Phase 1 (Nov 2024) – TTF with 5-day hypofractionated radiosurgery + chemotherapy.
• Phase 1 (May 2025) – TTF with a personalised tumor vaccine for newly diagnosed GBM.
• Phase 1 (June 2024) – TTF with chemotherapy and bevacizumab in pediatric high-grade glioma.
• Real-World Data Study (2024) – Analysing Optune’s intervention timing in newly diagnosed GBM.
• Phase 1 (Dec 2025) – Testing Optune preoperatively and pre-radiotherapy in new GBM diagnoses.

We also approached NHSE to explore direct commissioning of Optune, but they declined, advising that NICE should conduct an appraisal.

Conclusions

The evidence supporting TTF’s impact and international experience is clear. TTF is not suitable for all patients—the TIGER study suggests ~40% decline its use—but there are UK patients who would opt for TTF if given the choice, and evidence indicates a significant survival benefit. Trial data also suggests TTF does not negatively impact quality of life, and long-term use is feasible.

Some clinicians have described TTF as “too much hassle” for patients. While it is inconvenient, our experience with the TTF Support Group shows that patients find ways to incorporate it into their daily lives. More importantly, we believe this decision should rest with patients themselves.

The survival benefit of TTF is well-documented. Future trials will explore its combination with additional treatments, but evidence for its use with standard therapy is already established. Without reimbursement, the UK remains a less attractive site for ongoing trials. In contrast, Germany is reimbursing the TTF component of EF-41, demonstrating a commitment to innovative cancer treatment that the UK risks falling behind on.