KIT (receptor tyrosine kinase) mutations occur in 15% of acral and mucosal melanomas. PIANO
is a single arm, phase II, open-label, multicentre study to evaluate the efficacy and safety
(plus molecular basis of such effects) of the KIT inhibitor PLX3397 (developed by Plexxikon)
in advanced KIT mutated acral and mucosal melanoma.
In this trial a total of 24 patients (9 in the first stage and 15 in the second stage) will
receive treatment over a 24 month recruitment period.
Following consent and successful screening, patients will receive PLX3397 capsules 1000mg/day
as monotherapy, and will remain on therapy as long as they are deriving clinical benefit.
Patients will be seen every 4 weeks during treatment to monitor response and toxicity.
Routine blood tests will be carried out at all visits and pharmacokinetics/pharmacodynamics
sampling (1 x 8 milliliter(ml) whole blood sample) will be done pre-dose on Day 1 and Day 15,
frozen and stored locally and sent to Plexxikon's vendor for central analysis at the end of
the study. Imaging will be carried out every 12 weeks to monitor response. The first 9
patients will also receive two [18F]-fluorodeoxyglucose (FDG) PET scans (baseline and at Day
15).
From specific named participating sites, 12 patients will provide additional (optional)
consent to take part in translational research. 5 of these patients will have a fresh tumour
biopsy taken at baseline, at day 15 and upon disease progression. The same 5 patients plus an
additional 7 patients (to give a total of 12 patients) will also donate blood samples at
baseline, 2 weeks, 12 weeks and on disease progression for the evaluation of circulating
tumour cells and circulating free tumour DNA.
All patients will be followed up every 6 months until death or for 12 months after the last
patient has discontinued study treatment.