Cancer researchers, drugmakers and Wall Street analysts converged in Madrid this past weekend for the European Society of Medical Oncology meeting, or ESMO, the continental counterpart to the U.S.'s ASCO, held each summer in Chicago.
Data showed promise and progress across cancer types, with particularly striking figures in survival among breast cancer patients in one Roche study. Immunotherapy, the harnessing of the immune system to fight cancer, also remained front and center.
Here's what Wall Street's buzzing about on Monday:
The Swiss drugmaker presented longer-term data on its breast cancer drug Perjeta, approved in 2012. The medicine extended survival by 15.7 months when added to Herceptin and the chemotherapy docetaxel, compared with Herceptin and chemotherapy alone, in patients with genetically defined breast cancer that's spread, Roche said.
The lead author of the study, Sandra Swain of Medstar Washington Hospital Center, called the results unprecedented.
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"This is the kind of survival improvement for which we have worked, and this data will be incredibly meaningful to patients and their families," Swain said in a statement.
Patients taking the triple combination had a median overall survival of 56.5 months, compared with 40.8 months on Herceptin and chemotherapy alone. Perjeta was approved in 2012 based on data showing it improved another metric, progression-free survival, to 18.5 months from 12.4 months.
Progression-free survival is a measure of whether cancer has progressed; overall survival is the key metric for showing whether cancer drugs work to extend life, but it takes longer to assess in clinical trials.
Both Perjeta and Herceptin, which was approved in 1998 and drew 6.1 billion Swiss francs ($6.4 billion) in 2013 sales for Roche, target a protein called HER2 that's expressed in about 20 percent of breast cancers. Overall, breast cancer is the second-leading cause of cancer death among women after lung cancer, with about 232,670 new cases and 40,000 deaths expected in the U.S. in 2014, according to the National Cancer Institute.
Merck received FDA approval of Keytruda, the first in a new class of immunotherapy drugs aimed at a target called PD-1, earlier this month in advanced melanoma. Data at ESMO show it may have promise in gastric, bladder, lung and other cancers, as well.
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Keytruda, also known as pembrolizumab, produced a 31 percent overall response rate in a small study in advanced gastric cancer, Merck said. The drug was tested in patients whose cancer tested positive for a marker called PD-L1. Twelve people out of 39 responded to the drug, and 11 of those 12 remain on therapy.
"Although gastric cancer is a relatively small market, there is significant unmet need," BMO Capital Markets analyst Alex Arfaei wrote in a research note Monday. Gastric cancer, he said, is the fifth-most common cancer in the world and the third-leading cause of cancer death.
The company also presented data Monday in bladder cancer, the ninth-most commonly diagnosed cancer worldwide, according to ESMO. There are more than 380,000 new cases and 150,000 deaths each year.
"No major progress has been made for more than a decade," Maria De Santis, an oncologist with Kaiser Franz Josef Hospital in Vienna, said in an ESMO statement.
Merck's Keytruda produced a 24 percent response rate in a trial in an advanced form of the disease presented this weekend, and the company said it plans to start a late-stage trial in the indication this year. The conference also highlighted a drug from Roche, MPDL3280A, which showed a 43 percent response rate in a recent study.
Merck also had data on Keytruda in lung and head and neck cancers, which John Boris, an analyst with SunTrust Robinson Humphrey, described as "competitive" and "encouraging."
British drugmaker AstraZeneca, which spurned an almost $120 billion bid from Pfizer earlier this year, presented updated data from an ongoing study of its drug AZD9291 for non-small cell lung cancer. Investors are watching for read-throughs to smaller drugmaker Clovis, which is developing a competing drug called CO-1686.
The AstraZeneca data, Citi analyst Yaron Werber said in a research note Sunday, "shows slight improvement," but an update expected in mid-November from Clovis is needed to assess where the competition stands.
Patients taking AZD9291 lived for a median 9.6 months without their cancer progressing. JPMorgan analyst Cory Kasimov said the data may bode well for Clovis's drug, which he notes has an estimated time of more than a year before progression.
AstraZeneca also presented data in immunotherapy, with its combination of MEDI4736 and tremelimumab appearing "to be better tolerated than Bristol-Myers's Opdivo plus Yervoy," Leerink analyst Seamus Fernandez wrote in a research note Sunday.
OncoMed presented data from early trials of its drug demcizumab in non-small cell lung cancer and pancreatic cancer that showed "encouraging activity," according to Peter Lawson at Mizuho Securities.
Puma reported data from a mid-stage trial of its drug neratinib in patients with non-small cell lung cancer who have the HER2 mutation. Eric Schmidt, an analyst with Cowen, said the results show the drug's side effect of diarrhea may be controllable with use of the medicine loperamide. He said that while the efficacy data "fell a bit below investor expectations," the safety results are impressive enough to support his $5 billion annual sales estimate in another indication, breast cancer.
Ariad updated results from its ongoing early-stage trial in non-small cell lung cancer. Its drug, AP26113, produced a 72 percent response rate in patients whose cancer tested positive for a mutation called ALK, the company said.
Lung cancer is the second-most common cancer in both men and women, other than skin cancer, and is the leading cause of cancer death, according to the American Cancer Society. It estimates there will be about 224,210 new cases of lung cancer in the U.S. this year, and about 159,260 deaths. Non-small cell is the most common form of lung cancer, accounting for about 9 of 10 cases, according to the ACS.
Endocyte also had data on its drug vintafolide in non-small cell lung cancer. While the mid-stage study "was officially a negative trial, there was a strong signal of improved survival in a large pre-specified subset of patients," Citi analyst Jonathan Eckard wrote in a research note Sunday. The results could lead to a later-stage study, Eckard said.
Finally, Exelixis gained in trading early Monday on results of a late-stage study of its drug cobimetinib in combination with the Roche drug Zelboraf in melanoma. The study met its goal in helping patients live longer without their cancer spreading, at a median 9.9 months for the combination versus 6.2 months for Zelboraf alone.