PracticeUpdate: Could you discuss the DESTINY-Lung01 trial?
Dr. Henry: LBA 45, titled "Primary data from DESTINY-Lung01 trial, phase two trial, trastuzumab deruxtecan." So, in the States, it's marketed as Enhertu, for HER2-mutated non-small cell lung cancer. Why use this drug? Is this a problem? Well, 3%, a small number but a real number, of non-small cell lung cancer patients are HER2 positive. So this study addressed those; these patients were refractory or progressed on first-line therapy: 91 patients, not bad to find that many, were in the study and it had a 54% response rate.
So really an incredible response for a very niche, small market, but a good one. We thought these were compelling results for this special patient population who are looking for something to work and this did work.
PracticeUpdate: How does the candidate drug help in this mutated lung cancer?
Dr. Henry: This drug, this medication is a HER2-directed therapy with deruxtecan, which gets into the cell and diffuses out; some of the other HER2-directed or trastuzumab-directed therapies are locked in the cell. This might come out of the cell and kill the immediate area so it's kind of a two-fer, this drug—directed plus a little bit to the immediate area for the HER2-positive lung cancer.
PracticeUpdate: Could you tell us more about the results and how that might impact clinical practice moving forward?
Dr. Henry: In this niche population of HER2 positive, which is only 3% of non-small cell, 54% response rate and the disease control rate was in the eighties. Median duration of response was 9.3 months, progression-free survival months 8.2, median overall survival 17.8 months, very acceptable potential for toxicity. So these are compelling results in this small driver-mutated lung cancer HER2 positive. So another reason why we look for all these driver mutations in all of our lung cancers is to find those where we can have an actionable medication. This would be one, a really important one, for this small set of patients.