CHELSEA — Pfizer The company announced Friday that its drug for an advanced form of lung cancer had shown promising long-term results in a late-stage study, which could help establish it as a new standard treatment for the disease.
The company's drug helped patients live longer without their cancer progressing, and most people benefited for more than five years. The drug, called Lorbrena, also lowered the risk of cancer progressing in patients' brains.
Lorbrena is already approved in the United States to treat adults with advanced non-small cell lung cancer who have a mutation in a gene called ALK. Only about 5% of all patients with non-small cell lung cancer have this mutation, which causes abnormal growth and spread of cancer cells.
However, that means that 72,000 people worldwide are diagnosed with this particular form of lung cancer each year, according to a Pfizer press release. This cancer is typically aggressive and often affects younger people, the company added.
In a broader sense, non-small cell lung cancer is a common form of the disease.
Lorbrena is specifically approved as a first-line treatment for this form of lung cancer, meaning patients taking it have not received any other therapy. But Pfizer's drug is not currently considered standard treatment – or the most appropriate and widely used – for this disease.
The company expects this to change with the new five-year data on the drug.
“In cancer medicine in general, you always want to give the best drug first. That is why we believe that these data … will lead to [Lorbrena] “It will become a standard first-line treatment for this particular form of lung cancer,” said Chris Boshoff, chief oncologist at Pfizer, in an interview with CNBC.
The new five-year data come from the same Phase 3 trial that led to Lorbrena's U.S. approval. Pfizer will present the results on Friday at the annual meeting of the American Society of Clinical Oncology in Chicago, the world's largest cancer research conference. The data were also published in the Journal of Clinical Oncology.
Nearly 300 participants in the study received either Lorbrena or Pfizer's older lung cancer drug Xalkori. After five years, 50 percent of the study patients were still receiving Lorbrena, while 5 percent of patients were receiving Xalkori.
In the study, Lorbrena reduced the risk of developing cancer or death by 81% after five years compared to Xalkori.
About 60% of patients treated with Lorbrena survived after this period without their cancer getting worse, compared to only 8% of patients taking Xalkori.
Dr. David Spigel, scientific director of the Sarah Cannon Research Institute, called these results “the best we have ever seen” during a press conference ahead of the ASCO conference.
“We've never seen anything that comes close to this. Durable, progression-free survival events of this magnitude have not been seen with other great drugs that are out there,” Spigel said, referring to the rate of people who stayed alive without their cancer getting worse.
He pointed out that there are no head-to-head studies between Pfizer's Lorbrena and competing lung cancer drugs, including alectinib and brigatinib.
All three are called ALK inhibitors and are designed to block the mutations in the ALK gene that are associated with abnormal cancer cell growth. Lorbrena is considered a new third-generation ALK inhibitor, while its two competitors are second-generation.
But Spigel added that it was “hard to believe” that Lorbrena would perform worse in a direct comparison with these drugs.
Pfizer's other drug, Xalkori, is also an ALK inhibitor, but is no longer used in the US
Lung cancer with the “ALK-positive” mutation is also particularly prone to spreading to the brain. About a quarter or more of patients can develop brain metastases – when cancer cells spread from their original part of the body to the brain – within the first two years after diagnosis.
Lorbrena reduced the risk of developing brain cancer by 94 percent compared to Pfizer's old drug. Only four of the 114 patients taking Lorbrena developed brain metastases within about 16 months, compared with 39 of the 109 patients taking Xalkori.
Lorbrena is effective in preventing and treating brain metastases because it can cross a membrane called the blood-brain barrier and enter the brain, something not all medications can do.
Spigel called this another “stunning finding” because the development in the brain “is pretty bad for patients and we are desperately trying to prevent or treat it.”
No new safety issues were reported for Lorbrena. The most common side effects included swelling, weight gain, changes in perception and mood, and high blood cholesterol.
But Spigel described the cognitive problems associated with Lorbrena as “unusual” because they are not seen in its competitors.
In a note Thursday ahead of the data's release, Dr. Andrew Berens, an analyst at Leerink Partners, said he believes Lorbrena's central nervous system side effects are partly why it is often used as a second-line rather than first-line treatment for this advanced form of lung cancer. These changes in cognition and mood lead to “a lower quality of life for patients,” he said.
However, Pfizer's Boshoff said that once doctors start using Lorbrena for the first time, they will be better able to cope with any specific side effects of the drug.
He noted that training doctors to deal with side effects will be an important part of the “relaunch” of Lorbrena after the publication of the new data.
