Pfizer's targeted drug knocks out child cancers in small study

Some of the biggest headlines coming out of the massive ASCO abstract release aren't focused on a promising experimental treatment. They're about Pfizer's ($PFE) recently approved treatment Xalkori. Now targeted at non-small-cell lung cancer tumors with ALK gene abnormalities, Xalkori was tested in children with rare cancers also linked to those defects. And its success in those kids illustrates how targeted drugs can progress beyond their initial uses to other cancers with similar genetic characteristics.

The small study tested Xalkori in 70 children with a variety of cancers. It benefited some patients in every disease type, but the most dramatic results came in kids with anaplastic large-cell lymphoma, a cancer known to have ALK rearrangements in some patients. Of 8 children with ALCL, 7 had a complete response to Xalkori. After treatment, no trace of their cancer could be seen on imaging scans.

Experts immediately applauded the Phase I results, while cautioning that questions about long-term response and side effects remain. American Society of Clinical Oncology President Michael Link told Reuters that the response rate was "pretty phenomenal." A pediatric oncologist himself, Link said, "The durability of the response is pretty amazing." Yael Mosse, lead author of the study, told Bloomberg, "[T]hese are very promising results for kids who historically have had very few options and no hope."

No drug is held more dear than one able to treat dying children. Thanks to developing knowledge about cancer's genetic drivers, pediatric testing of cancer drugs may well accelerate. Pfizer's Rob Sweetman told Bloomberg that cancer trials in children and adults "used to operate in separate universes. Now we understand these molecular drivers that are connecting these two that weren't as obvious before."

The next step, Mosse says, is a late-stage trial of Xalkori in children with lymphoma, which her team plans to begin by year's end. More work on children with neuroblastoma is also planned. While this latest study wasn't restricted to kids who tested positive for ALK abnormalities, future trials will focus on children with those mutations, Mosse told Reuters.

- check out the Reuters piece
- see the Bloomberg story
- get more from the Wall Street Journal

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