- Strong clinical results from AstraZeneca plc's cancer drugs Imfinzi and Tagrisso could give the British drugmaker much-needed momentum in lung cancer and help ease the sting of a damaging setback in the closely watched MYSTIC study this past July.
- Imfinzi, AstraZeneca's PD-L1 inhibitor, cut the risk of disease progression by nearly half in patients with Stage 3, unresectable non-small cell lung cancer (NSCLC), according to data presented over the weekend at the annual meeting of the European Society of Medical Oncology (ESMO).
- While the market for locally advanced lung cancers is smaller than in metastatic disease, Imfinzi is the first immuno-oncology agent to demonstrate a benefit in this setting. AstraZeneca believes its success here put it two to three years ahead of rivals like Bristol-Myers Squibb Co. and Merck & Co., who currently have a sizable advantage in advanced lung cancer.
AstraZeneca came into ESMO still suffering the ill effects to investor confidence of Imfinzi's (durvalumab) disappointing failure in first-line treatment of advanced NSCLC.
While that failure will crimp AstraZeneca's chances of quickly catching competitors in that market, the successes of Imfinzi and Tagrisso in the PACIFIC and FLAURA studies, respectively, could help it carve out its own niche.
In PACIFIC, AstraZeneca pitted Imfinzi against placebo in patients with Stage 3 NSCLC that can't be removed through surgery and hadn't yet progressed following standard-of-care treatment.
Unlike advanced or metastatic disease, Stage 3 cancers haven't spread to other organs in the body. In lung cancer, Stage 3 disease represents about one-third of total NSCLC incidence, according to AstraZeneca.
Treatment with Imfinzi led to a median progression-free survival of 16.8 months versus 5.6 months for placebo — a risk reduction of 48%.
"Overall survival data are awaited, but the magnitude of progression-free survival benefit supports this combination as a new standard of care," said Pilar Garrido, head of the Thoracic Tumour Section at the Ramon Y Cajal University Hospital in Madrid, Spain, in a statement provided by ESMO.
AstraZeneca also delivered impressive results from its Phase 3 FLAURA study of Tagrisso (osimertinib) in first-line treatment of NSCLC patients who have a specific mutation of the epidermal growth factor receptor (EGFR).
Tagrisso beat out current standard-of-care treatments Tarceva (erlotinib) and Iressa (gefitinib), extending progression-free survival to a median of 18.9 months versus 10.2 months on either of the comparator drugs. Notably, Tagrisso's benefit was consistent in patients with brain or central nervous system metastases, which are common in patients with EGFR-mutated NSCLC.
Adverse event rates were lower in the Tagrisso arm than in the comparator arm, further adding to Tagrisso's edge.
Strong results in the FLAURA study are important, as AstraZeneca hopes to make the drug a backbone treatment across all lines of therapy for EGFR-mutated lung cancer.
Analysts were largely positive on the study results. Jeffery Holford of Jefferies, an investment bank, believes the PACIFIC and FLAURA data will set both Imfinzi and Tagrisso up to become the gold standard for treatment of Stage 3 NSCLC and EGFR-mutated NSCLC, respectively.
AstraZeneca shares were up nearly 2% Monday morning, the first day of trading since announcement of the study results.