Clinical research program

of FLASH therapy at CHUV


Professor Jean Bourhis, Chairman of Radiation Oncology, CHUV

FLASH radiotherapy is a new form of radiotherapy, exceptional in that it is delivered in a few milliseconds, instead of minutes. It provides a remarkable sparing of healthy normal tissues, while maintaining intact its level of therapeutic effect on tumors.

In 2018, a compassionate treatment of a first patient with FLASH therapy was performed successfully at CHUV for a patient with a refractory skin lymphoma. This first attempt showed that FLASH therapy was feasible and safe, prompting rapid translation of FLASH therapy in cancer patients. Based on its pioneer role, its unique expertise and international leadership on FLASH therapy, the Lausanne University Hospital (CHUV) is now engaged in an intensive program for clinical translation of FLASH therapy. This clinical translation will be performed in 3 complementary phases that are being run in parallel.

First phase: depth of treatment up to 2.7 cm in tissues for FLASH therapy of skin cancers

Due to technical challenges, the first clinical prototype which is being used for clinical translation at the CHUV is only able to treat superficial skin cancers (up to 2.7 cm deep). This prototype has been provided to the CHUV by the IntraOp Medical Corporation (California, USA) in the frame of a research collaboration to accelerate the development of FLASH radiotherapy toward first human clinical trials.

In this frame, two clinical trials are about to start, the first for skin metastases of melanomas refractory to systemic treatments and the second one a randomized trial comparing FLASH therapy to conventional radiotherapy for superficial skin cancers. These two clinical trials are expected to provide a first proof of concept that FLASH therapy is superior to normal radiotherapy in patients. The Biltema Foundation, through the ISREC Foundation, is one of the major funding institutions for this phase of the program, but not the only one, as mentioned in the table below.

Second phase: depth of treatment up to 3.2 cm in tissues for intra-operative FLASH therapy

The second phase of the program will serve to evaluate the use of FLASH therapy delivered at the time of surgery for tumors that cannot be completely resected by the surgeon, in order to increase the general curability of the surgical procedure. FLASH intra-operative radiotherapy (FLASH IORT) will be performed with a second clinical prototype, the so-called the FLASH-KNIFE provided to the CHUV by the PMB corporation (Peynier, FRANCE). There is a long-standing history of collaboration on FLASH therapy between PMB and the CHUV which started in 2013. The Biltema Foundation is not involved in this phase of the program.

Third phase: treatment of deep-seated tumors for all types of cancers (CERN-CHUV project)

The third phase of the program is the most avant-garde and the most important one. Together with the CERN (European Organization for Nuclear Research), the CHUV is designing and will build a unique clinical demonstrator, which will be able to treat all types of deep-seated tumors and hence all types of cancers deep within tissues with FLASH therapy.

This phase of the program will be exclusively funded by the Biltema Foundation, along with the precious support of ISREC.

Interview (in French) with Prof. Pierre-Marie Glauser, President of the ISREC Foundation