Solar-1 trial for pi3kca mutation

Smellimd82

hello! Hope everyone is well after Thanksgiving. My best friend recently experience progression amd learned that she has a pi3kca mutation which is the most common mutation in metastatic breast cancer. It also leads to quicker progression while on AI. I have been on able to find anyone else on this or similar trials. Is anyone here on this trial or knowsof someone who is?

Bestbird

I am sorry to hear about your friend, and it is very loving of you to reach out on her behalf.

Thus far therapies that have targeted the Pi3kca mutation have not appeared to be terribly effective in mbc patients, although the search continues and an experimental drug called Alpelisib may hold promise.

I might also advise that not everyone who has the mutation progresses quickly on AI's, and your friend may do well on them for quite some time if she is hormone receptor positive and postmenopausal! " Overall, it appears that PIK3CA mutations are most likely found in tumors with less aggressive characteristics, especially estrogen receptor (ER)-positive, luminal A tumors." From: http://link.springer.com/article/10.1007/s12609-016-0215-6

Cure-ious

Hi S-

Sorry to hear about your friends' progression- I also try to follow this area, because PI3K mutations are indeed a common way that breast cancers eventually mutate to resist estrogen (AI) inhibitor therapy. Inhibiting the PI3K kinase is known to reverse the resistance to AIs in the lab, so the hope would be to down-regulate that pathway and restore sensitivity to AI therapy again. There was a bit of preliminary data presented awhile ago indicating that the response rate for the new drug Taselisib (response rate 41%) looks better than for Apelisib (response rate 25%), (http://www.datamonitorhealthcare.com/taselisib-shows-promise-in-relation-to-other-pi3k-inhibitors-for-hrher2-breast-cancer-patients/ ) but those are based on small patient numbers that may not hold up in later updates, and hopefully we hear more about it in the upcoming San Antonio meeting. Taselisib is being tested in the large phase III SANDPIPER trial, and is the topic on another thread if you search for it- somebody in that trial did post there, and it would be good to get an update from her- anyway, anyway, she did indicate that the drug does have side effects, perhaps comparable (though hopefully better!) than affinitor..