Stuart Lipton, via Scripps Research

Stu­art Lip­ton of­fers a new pos­si­ble rea­son why all the Alzheimer's drugs have failed

There are a few com­mon­ly trot­ted out rea­sons for why vir­tu­al­ly every Alzheimer’s drug of the last two decades has failed: Maybe the tri­als didn’t start ear­ly enough in the course of dis­ease, or maybe they didn’t go af­ter the right group of pa­tients?

As com­pa­nies have start­ed ear­li­er and on more se­lect groups of pa­tients, an­oth­er con­clu­sion has grown in­creas­ing­ly pop­u­lar: Maybe they’ve all gone af­ter the wrong tar­get. Maybe clear­ing the mis­fold­ed plaques that buildup in pa­tients’ brains, as these ther­a­pies have, just wipes away one symp­tom of the dis­ease but not the root cause.

Stu­art Lip­ton, though, has an al­ter­na­tive ex­pla­na­tion. A lead­ing de­men­tia ex­pert who helped de­vel­op the the last FDA-ap­proved Alzheimer’s drug, he is pub­lish­ing new re­search this week show­ing that the an­ti­bod­ies com­pa­nies de­vel­oped might be hav­ing an un­in­tend­ed side ef­fect that un­der­cuts any ben­e­fit they of­fer.

Amy­loid-clear­ing an­ti­bod­ies, he wrote in a pa­per for the Pro­ceed­ing of the Na­tion­al Acad­e­my of Sci­ence, might be set­ting off dan­ger­ous in­flam­ma­tion that, in a cru­el bit of irony, has­ten neu­ro­log­i­cal de­cline. Lip­ton called the re­sult para­dox­i­cal.

“We re­al­ized that it’s pos­si­ble these hu­man tri­als, many of which have failed, might be in part fail­ing be­cause they’re para­dox­i­cal­ly in­duc­ing more in­flam­ma­tion in the brain,” he told End­points News, “even though they’re get­ting rid of the pro­tein, which may be a good thing.”

Dorit Trudler

The re­search be­gan when a post­doc at Lip­ton’s Scripps In­sti­tute lab, Dorit Trudler, at­tempt­ed to make the in­nate im­mune cell of the brain, an oc­to­pus-look­ing goop called the mi­croglia, in the lab. It’s a dif­fi­cult task be­cause mi­croglia don’t come from the same lin­eage of stem cells in the bone mar­row that the rest of the im­mune sys­tem, B cells and T cells and macrophages, do.

In­stead, it comes from the yolk sac that bathes em­bryos in ear­ly de­vel­op­ment, mi­grat­ing from the sac to the brain. By giv­ing hu­man-de­rived stem cells a se­ries of mol­e­c­u­lar sig­nals, Trudler turned them in­to a clus­ter that re­sem­bled a yolk sac and, from it, de­vel­oped cells that, based on the mR­NA they ex­press, were in­dis­tin­guish­able from mi­croglia re­moved from hu­mans.

“They match as close­ly as pos­si­ble,” Lip­ton said.

Be­cause hu­man mi­croglia are dif­fi­cult to pro­duce, drug re­searchers have his­tor­i­cal­ly used mouse mod­els to see how the im­mune cells re­spond to drugs. Lip­ton and Trudler, though, were able to sim­u­late how hu­man mi­croglia re­spond in the brain.

They found that if you ex­posed these mi­croglia to ei­ther al­pha synu­cle­in, the hall­mark mis­fold­ed pro­tein in Parkin­son’s, the mi­croglia sent off in­flam­ma­to­ry sig­nals. And if you added amy­loid-be­ta, the in­flam­ma­tion wors­ened.

Fi­nal­ly, they man­aged to ob­tain an­ti­bod­ies that com­pa­nies had de­vel­oped to bind to and clear those mis­fold­ed pro­teins. (Lip­ton de­clined to say which an­ti­body it was, ex­cept that, de­spite his best ef­forts to con­vince the drug­mak­er, it wasn’t Bio­gen’s ad­u­canum­ab, the con­tro­ver­sial can­di­date now be­fore the FDA.)

To their sur­prise, the an­ti­bod­ies suc­cess­ful­ly bind­ed to the mis­fold­ed pro­tein but that didn’t help in­flam­ma­tion. “Rather than make things bet­ter, it ac­tu­al­ly made things worse,” Lip­ton said.

By look­ing at hu­man­ized mice that had both hu­man and mice mi­croglia, Lip­ton’s team found that the pro-in­flam­ma­to­ry re­sponse was unique to the hu­man cells, mean­ing drug­mak­ers wouldn’t have seen it in the trans­la­tion­al stud­ies. They’re still not sure why it’s caus­ing in­flam­ma­tion, but they showed the ef­fect with mul­ti­ple dif­fer­ent an­ti­bod­ies that tar­get mul­ti­ple dif­fer­ent pro­teins and they’ve nailed down the path­way, NL­RP3, that’s in­volved.

Still, Lip­ton said, they don’t nec­es­sar­i­ly have to fig­ure out the ex­act mech­a­nism. He says you could imag­ine giv­ing these amy­loid-clear­ing drugs in com­bi­na­tion with a drug that blocks in­flam­ma­tion, al­low­ing doc­tors to clear out mis­fold­ed pro­teins with­out dan­ger­ous­ly turn­ing up the heat.

In fact, it’s what his lab is work­ing on right now.

“We’re hope­ful that we can maybe de­vel­op a drug in the near fu­ture that can off­set,” Lip­ton said.

Pi­o­neer­ing Click Chem­istry in Hu­mans

Reimagining cancer treatments

Cancer is a leading cause of death worldwide, accounting for nearly 10 million deaths in 2020, which is nearly one in six deaths. Recently, we have seen incredible advances in novel cancer therapies such as immune checkpoint inhibitors, cell therapies, and antibody-drug conjugates that have revamped cancer care and improved survival rates for patients.

Despite this significant progress in therapeutic targeting, why are we still seeing such a high mortality rate? The reason is that promising therapies are often limited by their therapeutic index, which is a measure of the effective dose of a drug, relative to its safety. If we could broaden the therapeutic indices of currently available medicines, it would revolutionize cancer treatments. We are still on the quest to find the ultimate cancer medicine – highly effective in several cancer types, safe, and precisely targeted to the tumor site.

Joshua Cohen (L) and Justin Klee, Amylyx co-CEOs

BREAK­ING: Af­ter long and wind­ing road, FDA ap­proves Amy­lyx's ALS drug in vic­to­ry for pa­tients and ad­vo­ca­cy groups

For just the third time in its 116-year history, the FDA has approved a new treatment for Lou Gehrig’s disease, or ALS.

US regulators gave the thumbs-up to the drug, known as Relyvrio, in a massive win for patients and their families. The approval, given to Boston-area biotech Amylyx Pharmaceuticals, comes after two years of long and contentious debates over the drug’s effectiveness between advocacy groups and FDA scientists, following the readout of a mid-stage clinical trial in September 2020.

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Ivan Cheung, Eisai US chairman and CEO

Bio­gen, Ei­sai re­fresh amy­loid hy­poth­e­sis with PhI­II show­ing Alzheimer's med slows cog­ni­tive de­cline

In the first look at Phase III data for lecanemab, Eisai and Biogen’s follow-up Alzheimer’s drug to the embattled Aduhelm launch, results show the drug passed with flying colors on a test looking at memory, problem solving and other dementia metrics.

One of the most-watched Alzheimer’s therapies in the clinic, lecanemab met the study’s primary goal on the CDR-SB — Clinical Dementia Rating-Sum of Boxes — giving the biotech the confidence to ask for full approval in the US, EU and Japan by next March 31. The experimental drug reduced clinical decline on the scale by 27% compared to placebo at 18 months, the companies said Tuesday night Eastern time and Wednesday morning in Japan.

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Nooman Haque, head of life sciences and healthcare at Silicon Valley Bank, and John Carroll

I’m head­ed to Lon­don soon for #EU­BIO22. Care to join me?

It was great getting back to a live ESMO conference/webinar in Paris followed by a live pop-up event for the Endpoints 11 in Boston. We’re staying on the road in October with our return for a live/streaming EUBIO22 in London.

Silicon Valley Bank’s Nooman Haque and I are once again jumping back into the thick of it with a slate of virtual and live events on October 12. I’ll get the ball rolling with a virtual fireside chat with Novo Nordisk R&D chief Marcus Schindler, covering their pipeline plans and BD work.

Some­one old, some­one new: Mod­er­na pro­motes CTO, raids No­var­tis for re­place­ment amid pipeline push

Moderna CEO Stéphane Bancel made clear on the last quarterly call that “now is not the time to slow down.” On Thursday, he made a bit more room in the cockpit.

The company unveiled a new executive role on Thursday, promoting former chief technical operations and quality officer Juan Andres to president of strategic partnerships and enterprise expansion, and poaching a former Novartis exec to take his place.

Gilead names 'k­ing­pin­s' in coun­ter­feit HIV med law­suit

Gilead is mounting its counterfeit drug lawsuit, naming two “kingpins” and a complex network of conspirators who allegedly sold imitation bottles of its HIV meds, some of which ended up in US pharmacies.

The pharma giant on Wednesday provided an update on what it called a “large-scale, sophisticated counterfeiting conspiracy,” accusing two new defendants of “leading and orchestrating” a scheme to sell hundreds of millions of dollars in illegitimate drugs posing as meds such as Biktarvy and Descovy.

Vlad Coric, Biohaven CEO (Photo Credit: Andrew Venditti)

As Amy­lyx de­ci­sion waits in the wings, Bio­haven’s ALS drug sinks (again) in plat­form tri­al

The FDA’s decision on Amylyx’s ALS drug is set to come out sometime Thursday. In a space with few drugs, any approval would be a major landmark.

But elsewhere in the ALS field, things are a bit more tepid.

Thursday morning, Biohaven announced that its drug verdiperstat failed its arm of an ALS platform trial led by Massachusetts General Hospital. According to a press release, the drug did not meet its primary endpoint — improvement on an ALS functional status test — or any key secondary endpoints at 24 weeks. The trial had enrolled 167 patients, giving them either verdiperstat or placebo twice a day.

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Tar­sus looks to raise aware­ness of eye­lid mite dis­ease in cam­paign aimed at eye­care spe­cial­ists

Eyelid mite disease may be “gross” but it’s also fairly common, affecting about 25 million people in the US.

Called demodex blepharitis, it’s a well-known condition among eyecare professionals, but they often don’t always realize how common it is. Tarsus Pharmaceuticals wants to change that with a new awareness campaign called “Look at the Lids.”

The campaign and website debut Thursday — just three weeks after Tarsus filed for FDA approval for a drug that treats the disease.

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Marcelo Bigal, Ventus Therapeutics CEO

No­vo Nordisk joins No­var­tis, Roche in NL­RP3 are­na, bet­ting $70M cash on NASH, car­diometa­bol­ic us­es

As a drug target, the NLRP3 inflammasome has drawn serious interest from Big Pharma, inspiring a series of M&A deals from Novartis and Roche on top of venture investments by others. Now Novo Nordisk is jumping on the bandwagon — and the Danish pharma giant is taking the target where it knows best.

Novo Nordisk is getting its NLRP3 inhibitors from Ventus Therapeutics, a Versant-backed startup that set out to make some of the best NLRP3 drugs out there by incorporating new insights into the structure of the target complex.

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