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(Alliance News) - AstraZeneca PLC on Friday presented a slew of positive trial data on cancer drugs Enherto and Imfinzi at the 2020 American Society of Clinical Oncology ASCO20 Virtual Scientific program.
This included detailed results from the Destiny-Gastric01 phase 3 trial randomised controlled trial of Enhertu, the brand name for trastuzumab deruxtecan, in HER2-positive metastatic gastric cancer. Changes to the HER2 gene are associated with tumour growth.
These results showed that the drug "demonstrated a statistically significant and clinically meaningful improvement in objective response rate and overall survival" compared to chemotherapy.
The overall response rate was found to be 43% compared to 13% with chemotherapy. In total, 10 complete responses and 41 partial responses were seen in patients with Enhertu compared to no complete responses and 7 partial responses in chemotherapy patients.
Furthermore, patients treated with Enhertu had a 41% reduction in risk of death compared to chemotherapy.
FTSE 100-listed pharmaceutical company Astra is developing Enhertu along with Japanese peer Daiichi Sankyo Co Ltd.
Another trial, Destiny-CRC01, in HER2-positive metastatic colorectal cancer, found that Enhertu achieved a 45.3% tumour response rate. Objective response rate was the primary endpoint.
Destiny-CRC01 was a phase 2 trial in advanced colorectal cancer patients who had received at least two previous lines of standard treatment. Median progression-free survival was 6.9 months.
In HER2-mutant advanced non-small cell lung cancer, Enhertu "demonstrated meaningful clinical activity" according to interim analysis of Astra's phase 2 Destiny-Lung01 trial. The primary endpoint was overall response rate, which was found to be 62%.
For Imfinzi, the brand name for durvalumab, a phase 3 trial found that the drug - when combined with chemotherapy, etoposide plus either carboplatin or cisplatin - produced a sustained and clinically meaningful overall survival benefit. The Caspian trial was of adults with extensive-stage small cell lung cancer.
Caspian met is primary endpoint back in June 2019, reducing risk of death by 27%. This was the basis of the US Food & Drug Administration's approval for the drug in March 2020.
Following a media follow up of over two years, the most recent results shows that efficacy has been maintained, with patients continuing to have a 25% reduction in risk of death compared to just chemotherapy. The median overall survival was 12.9 months compared to 10.5 months with chemotherapy alone.
Around 22% of patients who had been treated with Imfinzi plus chemotherapy were still alive at 24 months versus 14% with chemotherapy alone. Of those patients treated with Imfinzi plus chemotherapy, 11% were alive and progression-free compared to 2.9% with just chemotherapy.
In another Imfinzi trial, Study 22, found "promising clinical activity and tolerability in patients with advanced hepatocellular carcinoma", the most common type of liver cancer. This was a phase 2 trial that involved another Astra drug, tremelimumab, added to Imfinzi.
The primary endpoint of Study 22 was to evaluate the safety of the drug, with all experimental arms finding " an acceptable profile" with no new safety signals found. Patients were given a single priming dose of tremelimumab added to Imfinzi every four weeks and achieved a median overall survival of 18.7 months. Overall survival was a key secondary endpoint.
Shares in Astra were up 1.8% at 8,857.36 pence in London on Friday afternoon.
By Anna Farley; annafarley@alliancenews.com
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