That he did this just a week and a half after a delicate surgery to remove a blood clot along with cancerous tissue in his brain is, well, vintage McCain. It was one more reminder of how tough the guy—who survived years in captivity as a prisoner of war and an earlier bout with melanoma—truly is.

The cancer McCain is now fighting, glioblastoma multiforme (or GBM), is brutal and aggressive, and the standard treatments in the clinic (surgery, radiation, and chemotherapy—typically with a drug called temozolomide) haven’t moved the needle much in terms of patient survival.

There are a number of reasons why GBM is so damn hard to treat, and I won’t go into them here. But one big challenge is structural: the blood-brain barrier (BBB). The BBB isn’t quite an anatomical wall, as many assume it to be, but rather a phalanx of tightly meshed cells and protein complexes. The net effect, however, is the same: The BBB restricts certain substances, including many larger molecules (such as the drug temozolomide), from passing into the brain from the bloodstream.

To get around this gatekeeper, researchers have tried a number of approaches—including attaching drugs to nanoparticles that might slip through the BBB. But another approach, serendipitously, hails from sharks. It turns out that these long-lived fishes, who are our ancient evolutionary cousins, share the core of an adaptive immune system with human beings.

Both sharks and humans make antibodies to invading antigens—with one key difference: Human antibodies are shaped a bit like a serving fork, with one prong being the so-called heavy chain, and the other the light chain. Shark antibodies have just the heavy chain, with an antigen-grabbing domain called a VNAR at the tip. VNARs, moreover, are small and soluble…and can pass through the blood-brain barrier. That makes them a possibly effective vehicle for ferrying drugs into the brain—a potential boon for the treatment of Alzheimer’s, Parkinson’s, other disorders, and cancers of the brain and central nervous system.

One biotech firm, Ossianix, is already hard at work developing a VNAR-based drug-delivery system, in collaboration with the global pharmaceutical company Lundbeck, which focuses on drugs for brain disorders. While we are still several years away, perhaps, from a suite of shark-antibody-connected drugs in the clinic, it’s a promising area for development.

More news on the GBM front: Tomorrow (Thursday) and Friday, the Parker Institute for Cancer Immunotherapy, is hosting a glioblastoma immuno-oncology research summit in Los Angeles—bringing together top industry and academic scientists to share their research.

So keep swimming, everyone. There’s hope for all of us shark cousins.

DIGITAL HEALTH

Your genome may be headed to Amazon's cloud. Genetic testing is all the rage in biopharma these days, with players ranging from pharmaceutical giants to dozens of upstarts getting into the genomics game. One of the most-watched players in recent years has been Grail, an ambitious Silicon Valley firm working on "liquid biopsy" technology that could, theoretically, be used to test for early signs of cancer in through a simple blood draw. But getting such a product to market will require expansive clinical testing—testing that will produce mountains of genomic data. And that data needs to be stored somewhere. Enter: Amazon, which CNBC reports invested in Grail in the hopes that its cloud web services could eventually become a repository for all this information. (CNBC)

Cochlear's hearing implants work with the iPhone and iPad. Cochlear announced on Wednesday that its hearing implants will now work with the iPhone, iPad, and iPod devices without the need for an intermediary device (a step that's been necessary up until this point). "It's the first time people with an iPhone will be able to pick up the phone normally, or just listen to music, without any additional devices," Cochlear senior vice president Jan Janssen told Reuters in an interview. (Fortune)

INDICATIONS

Glaxo's new CEO makes her mark with a major restructure. British pharma giant GlaxoSmithKline is seriously shaking up (among other things) its R&D operation as part of a bid to realize one billion pounds in annual savings. It's one of the first major moves by new CEO Emma Walmsley, who previously used to head GSK's consumer health business. One sector that may be getting the axe? Glaxo's rare disease unit.

THE BIG PICTURE

Obamacare repeal 'vote-a-rama' continues in the Senate. After a dramatic procedural vote in the Senate yesterday afternoon, the Obamacare debate rages on in the Senate. What's still decidedly undecided is what the Senate may (or may not) finally pass. One health care bill—a new iteration of the Better Care Reconciliation Act (BCRA)—went down in flames yesterday. There are several other planned votes this afternoon on a range of repeal/replace bills, most of which are expected to fail. But these may, as I reported yesterday, amount to simple show votes before a final vote on a "skinny" Obamacare replacement that would repeal the health law's individual insurance mandate and not much else. And that in itself is likely a show vote since it has little chance of passing in the House; rather, it may provide an avenue for keeping the legislative process going, buying time to iron out a new Senate-House deal on health care. Where would that lead? As of now, nobody really knows. (Fortune)

Trump announces ban on transgender Americans serving in the military over "tremendous" medical costs. President Trump took to Twitter to announce that transgender people will no longer be allowed to serve in the military, reversing former President Barack Obama's administration's nixing of a ban on transgender troops. The reasoning? "Our military must be focused on decisive and overwhelming victory and cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail," said Trump. Just what are those tremendous medical costs, for services such as hormone therapy or surgery? About "0.005% to 0.017% of the department's overall health care costs," according to a 2016 study by the RAND Corporation. (Fortune)

REQUIRED READING

Sequoia and Andreessen Horowitz Are Secretly Backing This Cryptocurrency Hedge Fund, by Jen Wieczner

Chipotle Says the Recent Norovirus Outbreak Was Caused By a Sick Employee, by Reuters

Apple to Pay More Than $500 Million in Latest Patent Spat, by Don Reisinger

See Which U.S. Cities Have the Biggest Number of Millionaires, by Nicolas Rapp & Brian O'Keefe