Roche's Xofluza may give rise to re­sis­tant strains, rais­ing fears of a 'worst case sce­nar­i­o'

In 2018, Sh­iono­gi rolled out Xofluza in Japan as a one-dose kill for in­fluen­za, with Roche fol­low­ing suit in the US. Soon, though, Japan­ese reg­u­la­tors no­ticed the drug was lead­ing to re­sis­tant flu strains, and now a new study in Na­ture con­firms the drug leads to spe­cif­ic mu­ta­tions that may ham­per its promise to neu­tral­ize the virus in a sin­gle dose.

An­drew Pekosz John Hop­kins

“In a worst case sce­nario, these mu­ta­tions could ren­der the drug en­tire­ly use­less,” An­drew Pekosz, a mol­e­c­u­lar bi­ol­o­gist at Johns Hop­kins who was not in­volved in the study, told End­points News. “They haven’t yet, and it’s not clear why that’s been the case.”

No­tably, Pekosz said, the mu­tant virus­es have not spread ex­ten­sive­ly in hu­mans. Rather, re­searchers at the Uni­ver­si­ty of Wis­con­sin and the Uni­ver­si­ty of Tokyo took strains from pa­tients in Japan who had re­ceived Xofluza and found some con­tained mu­ta­tions to a struc­ture the virus us­es to repli­cate it­self, called the poly­merase com­plex.

Xofluza, or balox­avir acid, tar­gets this com­plex to kill the virus. When re­searchers test­ed the mu­tant strains in an­i­mal and cell lines, they found it was re­sis­tant to the drug and ca­pa­ble of spread­ing. Of 77 sam­pled chil­dren, 18 (23%) had mu­tant strains.

“This is not the first study, maybe one of the most ex­ten­sive ones, that show a sin­gle mu­ta­tion can cause re­sis­tance,” Pekosz said. “And those re­sis­tant virus­es still seem to have the abil­i­ty to repli­cate and spread just like the wild virus.”

Roche billed Xofluza as the first flu treat­ment ap­proved in 20 years and tout­ed the com­pli­ance ad­van­tages over its pre­de­ces­sor Tam­i­flu; One dose on one day as op­posed to 10 dos­es over 5 days. But re­sis­tance has been a con­tin­u­al prob­lem with such drugs. Most no­tably, the once-com­mon flu drug aman­ta­dine is no longer pre­scribed as vir­tu­al­ly all strains have be­come re­sis­tant.

As Xofluza neared ap­proval, re­searchers warned it may cause re­sis­tance. A New Eng­land Jour­nal of Med­i­cine ed­i­to­r­i­al pub­lished a month be­fore the drug’s US ap­proval found treat­ment led to “the emer­gence of vi­ral es­cape mu­tants with re­duced sus­cep­ti­bil­i­ty.”

“The is­sue for pub­lic health is whether these in­fluen­za virus­es with re­duced sus­cep­ti­bil­i­ty to balox­avir are trans­mis­si­ble,” wrote Tim­o­thy M. Uye­ki.

That ques­tion re­mains in­con­clu­sive, al­though the au­thors of the Na­ture study not­ed that one child who had not re­ceived Xofluza nev­er­the­less test­ed pos­i­tive for a re­sis­tant strain, “sug­gest­ing the pos­si­bil­i­ty of per­son-to-per­son trans­mis­sion of the vari­ant.”

For Pekosz, the ques­tions un­der­score the need for flu drug cock­tails that at­tack the virus from mul­ti­ple an­gles, like how doc­tors treat the HIV; If a virus needs two pre­cise mu­ta­tions to sur­vive and evolve, it’s much more less like­ly to.

“We’re mak­ing it too easy for the virus to es­cape,” he said.

How Pa­tients with Epilep­sy Ben­e­fit from Re­al-World Da­ta

Amanda Shields, Principal Data Scientist, Scientific Data Steward

Keith Wenzel, Senior Business Operations Director

Andy Wilson, Scientific Lead

Real-world data (RWD) has the potential to transform the drug development industry’s efforts to predict and treat seizures for patients with epilepsy. Anticipating or controlling an impending seizure can significantly increase quality of life for patients with epilepsy. However, because RWD is secondary data originally collected for other purposes, the challenge is selecting, harmonizing, and analyzing the data from multiple sources in a way that helps support patients.

Re­gen­eron's Evkeeza shows promise in curb­ing high triglyc­erides, but will ge­net­ic dis­par­i­ties lim­it use?

When Regeneron scored an early approval for lipid lowering antibody Evkeeza back in February, the drugmaker cracked open a new pathway to lower abnormally high cholesterol levels. Now, Regeneron is chasing high triglycerides as well with some promising mid-stage data — but will genetic restrictions limit the drug’s use?

Regeneron’s Evkeeza (evinacumab) cut median triglyceride levels by more than 800 mg/dL (57%) in patients with a rare disorder causing abnormally high triglyceride levels compared with an overall increase of 50 mg/dL (1.8%) in participants on placebo, according to Phase II data presented Sunday at the virtual American College of Cardiology meeting.

$DNA is once again on NYSE; FDA clears Soliris chal­lenger for the mar­ket; Flag­ship’s think­ing big again with eR­NA; and more

Welcome back to Endpoints Weekly, your review of the week’s top biopharma headlines. Want this in your inbox every Saturday morning? Current Endpoints readers can visit their reader profile to add Endpoints Weekly. New to Endpoints? Sign up here.

I still remember the uncertainty in the air last year when nobody was sure whether ASCO would cancel their in-person meeting. But it’s now back again for the second virtual conference, and Endpoints News is here for it. Check out our 2-day event reviewing the landscape of cancer R&D and send news our way.

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As­traZeneca's Farx­i­ga missed big on Covid-19 study, but it's tak­ing SGLT2 safe­ty da­ta as a sil­ver lin­ing

AstraZeneca hasn’t seen many setbacks in recent months for SGLT2 inhibitor Farxiga, which broke ground in heart failure and kidney disease regardless of diabetes diagnosis. But the British drugmaker had to admit defeat in taking Farxiga into Covid-19, but follow-up results add a bit of a silver lining to that trial’s safety data.

Of hospitalized Covid-19 patients dosed with AstraZeneca’s Farxiga, 11.2% experienced an organ failure or died after 30 days of therapy compared with 13.8% of those given placebo, according to follow-up data from the DARE-19 study revealed Sunday at the virtual American College of Cardiology meeting.

Pfiz­er, Bris­tol My­er­s' Eliquis flops in post-heart surgery pa­tients, spurring an 'un­ex­plained sig­nal' in cer­tain deaths

Pfizer and Bristol Myers Squibb’s non-warfarin blood thinner Eliquis has raced out to become the most prescribed drug of its class on the market — even overtaking warfarin’s long-time lead. But in tricky-to-treat patients after a valve replacement, an investigator-sponsored study couldn’t turn up benefit and raised a troubling safety signal.

Eliquis failed to show benefit over standard of care in preventing serious clinical outcomes after a transaortic valve replacement (TAVR) and was linked to an “unexplained signal” in a subset of populations with a higher rate of non-CV deaths who did not need blood thinners apart from the surgery, according to data presented Saturday at the virtual American College of Cardiology meeting.

Gene ther­a­py from Bio­gen's $800M buy­out flops in mid-stage study, deal­ing blow to new am­bi­tions

The #2 candidate from Biogen’s $800 million ocular gene therapy buyout has failed in a mid-stage trial, dealing an early blow to the big biotech’s plans to revitalize its pipeline with new technologies.

Biogen announced that the candidate, an experimental treatment for a rare and progressive form of blindness called X-linked retinitis pigmentosa (XLRP), failed to sufficiently improve vision in patients’ treated eye — patients only received an injection in one eye — after a year, on a standard scale, compared to their untreated eye. The company said they saw “positive trends” on several secondary endpoints, including visual acuity, but declined to say whether the trial actually hit any of those endpoints.

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Michael Dell (Richard Drew, AP Images)

'Dude, you're get­ting a Del­l' — as a new deep-pock­et biotech in­vestor

What happens when you marry longtime insiders in the global biotech VC game with the family fund of tech billionaire Michael Dell, a synthetic biology legend out of MIT and Harvard and the former director of the NCI?

Today, the answer is a newly financed, $200 million biotech SPAC now cruising the industry for a top player interested in finding a short cut to Nasdaq.

Orion Biotech Opportunities priced their blank check company today, raising $200 million with Dell’s multibillion-dollar MSD group’s commitment on investing another $20 million in a forward-purchase agreement.

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Bris­tol My­ers backs up its case for heart drug mava­camten as FDA weighs app in car­diomy­opa­thy

When Bristol Myers Squibb signed off on its $13 billion acquisition of MyoKardia back in October, it was making a big bet that lead drug mavacamten could prove a game changer in cardiac myopathy. Now, with the drug up for FDA review, Bristol Myers is backing up its case with new quality of life data.

Patients dosed with myosin inhibitor mavacamten posted a clinically significant increase in scores on the Kansas City Cardiomyopathy Questionnaire, a catch-all summary of symptoms and quality of life markers, over placebo at 30 weeks, according to data from the Phase III EXPLORER-HCM study presented Saturday at the virtual American College of Cardiology meeting.

Vas Narasimhan (Photographer: Simon Dawson/Bloomberg via Getty Images)

No­var­tis whiffs on En­tresto study af­ter heart at­tacks — but that does­n't mean it's go­ing down qui­et­ly

If Novartis learned one thing from its interaction with the FDA over its latest heart failure approval for Entresto, it was that missing a primary endpoint may not be the nail in the coffin. Now, Entresto has missed again on a late-stage study in high-risk heart patients, and it’s already sowing the seeds for a path forward regardless.

Novartis’ Entresto couldn’t best standard-of-care ramipril in staving off a composite of deaths and heart failure events in patients with left ventricular systolic dysfunction and/or pulmonary congestion who have had a prior heart attack, according to topline data from the Phase III PARADISE-MI study revealed Saturday at the virtual American College of Cardiology meeting.