THE ONGOING PHASE 2 STUDY NEOFOX
The phase 2 study NeoFox with Foxy-5 includes patients with stage II / III colon cancer, who at diagnosis are considered to have a high risk of recurrence after the primary tumour has been surgically resected. The assessment of the risk of recurrence is performed according to established assessment criteria. The aim of the study is to demonstrate that Foxy-5 reduces the risk of relapse, primarily in patients with low expression of WNT5A.
The study is currently underway at 28 hospitals in Spain (16) and Hungary (12).
To optimize the prevention of tumour spread, treatment with Foxy-5 starts in connection with the preliminary diagnosis. The ambition is to reach at least 9 treatments with Foxy-5 before surgery. The patient normally receives surgery within 4 weeks from the time of diagnosis and Foxy-5 treatment continues after surgery until chemotherapy is started (normally 1-2 months after surgery) or until the patient has received a maximum of 39 Foxy-5 treatments.
EVALUATION TO SEE INCREASED SURVIVAL
The primary evaluation in NeoFox is a comparison of the efficacy of Foxy-5 compared to a control group without Foxy-5 treatment. At the start of treatment, it is not known whether patients have high or low expression of WNT5A in the primary tumour. It is the levels of WNT5A in the resected primary tumours that will be decisive for whether the patients will be included in the statistical analysis of the study’s primary endpoints. Assessment of WNT5A expression is thus performed on all patients included in the study and is important for confirming the company’s assumption that approximately 50 percent of patients have a low expression of WNT5A.
The efficacy of Foxy-5 will be evaluated in at least 60 patients (30 treated with Foxy-5 and 30 in the control group) who after surgery have been assessed as having a high risk of recurrence and who have low expression of WNT5A.
The primary endpoints are ctDNA (circulating tumour DNA) and adverse events. ctDNA is a new technology where the presence of the surrogate marker ctDNA is measured by blood samples. It is a marker that can give an early signal for recurrence of disease. The level of ctDNA may indicate that the disease is recurring up to 30 months before visible metastases can be detected.
Effect regardless of level of WNT5A expression
In a separate comparison, the effect of Foxy-5 in all included patients is studied to assess the safety of the treatment, regardless of the level of WNT5A expression, but also to obtain an indication of whether Foxy-5 has a positive effect in patients with a higher WNT5A expression in the primary tumour. This approach is justified by the fact that at this stage it cannot be ruled out that patients who already have a higher expression of WNT5A may benefit from the treatment.
Patients are followed up for a total of 24 months after surgery, given that the majority of all recurrences normally occur within 12–24 months after diagnosis.
INTERIM ANALYSIS OF DATA ON 120 PATIENTS
The company is now planning to implement an interim analysis based on ctDNA from 120 patients followed up for a minimum of 6 months after surgery. This is to get an early signal about Foxy-5’s potential to reduce the risk of relapse.
The interim analysis, which is expected to be carried out at the end of 2022, will also guide the company in the total number of patients needed to be included in the study in order to achieve the primary objective of the study; to evaluate the treatment effect of Foxy-5 in at least 60 patients (30 treated with Foxy-5 and 30 in the control group) who after surgery were judged to have a high risk of relapse and who have low expression of WNT5A.