You should try asking on https://reddit.com/r/nonprofit or even reaching out to people at those foundations you mentioned for other diseases.

I'd start with a simple campaign page with your mission, your goals, some cute pics and some way to collect donations and capture emails. There's loads of fundraising CRMs out there. Givelively is a decent one and costs nothing but there's plenty of options. Even just a Facebook page could work.

As for how to acquire leads from scratch that's a tough one. Ads can work, you can also try reaching out to media orgs to try to get some airtime to talk about your campaign.