A new cancer medicine developed by AstraZeneca Plc and Daiichi Sankyo Co. seemed to fall short of investors’ expectations in partial results released early after a data leak at a medical conference.
(Bloomberg) — A new cancer medicine developed by AstraZeneca Plc and Daiichi Sankyo Co. seemed to fall short of investors’ expectations in partial results released early after a data leak at a medical conference.
The experimental drug was designed to stave off worsening of both lung and breast cancers for patients with few other options in a pair of highly anticipated studies. Astra shares dropped as much as 4.5% in London trading. Daiichi fell as 4.6% in Tokyo.
Designed to precisely target chemotherapy, the drug cut the risk of cancer getting worse or patients dying in the lung cancer study by 25% and in the breast cancer study by 37% compared with chemotherapy, according to abstracts posted late Tuesday on the website of the European Society for Medical Oncology. Neither included conclusive data on whether the drug could extend lives, a key metric.
In the lung study, patients on the experimental drug known as Dato-DXd experienced worsening cancer or death after an average of 4.4 months. That compares with an average of 3.7 months for those on chemotherapy. In the breast cancer trial, the difference was greater: 6.9 months for the experimental drug, compared with 4.9 months for chemotherapy.
The overall results gave “a negative impression,” Jefferies analyst Stephen Barker said, because the lung study didn’t match his anticipated results. The drug improved the time by 0.7 months compared with chemotherapy, when he anticipated 1.5-2 months, he wrote in a note to clients.
The worse-than-expected results from the lung study outweigh the in-line results from the breast study, he said.
Read More: Daiichi Sankyo Leads Japan Pharma Stocks Higher on Cancer Drug
Patients in both trials had already been through significant previous treatment, leaving them few options. Targeted drugs, known as antibody-drug conjugates, will make a big difference for the majority of patients with these conditions, according to Alessandra Curioni-Fontecedro, a professor at the University of Fribourg who wasn’t involved in the research.
“We need to know more about the side effects of this approach, but these findings are likely to change the standard of care for these patients,” she said.
There were three deaths related to adverse reactions among lung cancer patients who got the treatment, and two deaths in the chemotherapy group.
Some trial results became public earlier than expected after abstracts from the conference were leaked, leading the organizers to lift their embargo. A fuller picture will come on Oct. 23, when researchers present the data at the conference.
Investors have already had to deal with confusion surrounding the Daiichi-Astra drug, whose full name is datopotamab deruxtecan. It follows another targeted therapy from the partners, called Enhertu. In July, both companies’ shares plunged after what some analysts said was an unclear statement on the success of the lung cancer trial of Dato-DXd.
A separate study released ahead of the conference showed Johnson & Johnson’s Rybrevant in combination with the experimental treatment lazertinib beat Astra’s best—seller Tagrisso in helping patients live longer without their lung cancer progressing, and showed promise in extending their lives overall. The results suggest the J&J combination will “likely pose some competitive threat to Astra’s Tagrisso franchise, albeit less than perhaps feared,” Lucy Codrington and colleagues at Jefferies wrote.
–With assistance from Kanoko Matsuyama and Lisa Pham.
(Updates with J&J study in last paragraph)
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