Re­sis­tant to CAR-T ther­a­pies? It's the can­cer, not your im­mune sys­tem — study

Safe­ty con­cerns and man­u­fac­tur­ing short­com­ings aside, ex­ist­ing CAR-T ther­a­pies — No­var­tis’ Kym­ri­ah and Gilead’s Yescar­ta — sim­ply don’t work in 10% to 20% of pa­tients with B cell ma­lig­nan­cies. What fac­tors un­der­pin this re­sis­tance to CAR-T ther­a­py? The main cul­prit could be the can­cer cells them­selves, ac­cord­ing to a team of re­searchers at Penn.

CAR-T ther­a­pies are en­gi­neered to work in this way: Cells are ex­tract­ed from the pa­tient and then ma­nip­u­lat­ed in a lab where chimeric anti­gen re­cep­tors are added to di­rect the pa­tient’s own T cells to snuff out spe­cif­ic can­cer cells once re-in­fused back in­to the pa­tient. But in a frac­tion of pa­tients, the armed im­mune at­tack does not oblit­er­ate the dis­ease. By tar­get­ing CD19, a mark­er present on al­most all B cells, CAR-T ther­a­pies have shown re­mark­able po­ten­cy and dura­bil­i­ty in a num­ber of blood can­cers, in­clud­ing acute lym­phoblas­tic leukemia (ALL).

Re­search so far sug­gests that re­sis­tance to CAR-T ther­a­pies is re­lat­ed to the loss of CD19. When CD19 dis­ap­pears from leukemic cells, they be­come in­vis­i­ble to CAR-T ther­a­pies, not­ed the study’s co-se­nior au­thor Mar­co Ruel­la, an as­sis­tant pro­fes­sor of hema­tol­ogy-on­col­o­gy at the Uni­ver­si­ty of Penn­syl­va­nia, in an in­ter­view with End­points News.

“That ex­plains maybe half of the re­laps­es in leukemia and maybe a third in lym­phoma — so there is still a vast ma­jor­i­ty of pa­tients where we sim­ply don’t know what’s go­ing on,” he said.

An­oth­er fac­tor dri­ving re­sis­tance was dys­func­tion­al T cells, he added. “What we are hy­poth­e­siz­ing here is that there can be a third mech­a­nism…that even in the pres­ence of CD19 those leukemic cells are un­able to die when they are trig­gered by CAR-T.”

“The con­stant pres­ence of the leukemic cells that ba­si­cal­ly can­not die — they’re sort of high­landers — caus­es dys­func­tion in the T-cells. To start with — the CAR-T (cells) are okay — but then they keep try­ing to kill leukemic cells that in­trin­si­cal­ly can­not die, and then, over time, they be­come dys­func­tion­al.”

The find­ings were pub­lished on Thurs­day in Can­cer Dis­cov­ery, a jour­nal of the Amer­i­can As­so­ci­a­tion for Can­cer Re­search.

In the Penn study, re­searchers per­formed a genome-wide CRISPR/Cas9-based screen of an ALL cell line to iso­late path­ways as­so­ci­at­ed with re­sis­tance. Cells were edit­ed for loss of func­tion of sin­gle genes and com­bined with CAR-T cells for 24 hours to iden­ti­fy the path­way dri­ving the pri­ma­ry re­sis­tance. The in vit­ro da­ta showed that in the ALL cells that re­sist­ed the CAR-T at­tack, there was a short­age of genes in­volved in ac­ti­vat­ing the cell death path­way and a spike in genes nec­es­sary for evad­ing the cell death path­way.

In­stead of in­ter­ro­gat­ing sam­ples from pa­tients that have failed to ben­e­fit from CAR-T ther­a­pies, the plan was to mod­el a genome-wide re­sis­tance mech­a­nism and then con­firm it in pa­tients. Many pa­tients are now be­ing treat­ed with CAR-Ts, but still, the num­bers are lim­it­ed — so this ap­proach was used to dis­cov­er aber­ra­tions that the lim­it­ed num­ber of pa­tient sam­ples would not be pow­ered to iden­ti­fy, Ruel­la said.

“We start­ed with an un­bi­ased genome-wide ap­proach to study re­sis­tance and we saw that the new CRISPR/Cas9 genome knock­out li­braries were per­fect be­cause they would al­low you to ex­plore knock­outs in the whole genome and in­ter­ro­gate it for re­sis­tance to CAR-T.”

The find­ings were am­pli­fied in an­i­mal mod­els. The re­searchers then tried to make sense of the re­sults by us­ing pe­di­atric pa­tient sam­ples from pre­vi­ous CAR-T tri­als by an­a­lyz­ing the genes in leukemia cells and in T cells — pre- and post-in­fu­sion — from re­spon­ders and non-re­spon­ders. The da­ta were stark: pre­vi­ous­ly iden­ti­fied sig­nal­ing path­ways in can­cer cells were di­rect­ly as­so­ci­at­ed with re­spons­es to CAR ther­a­py, sug­gest­ing that death re­cep­tor sig­nal­ing is a key reg­u­la­tor of pri­ma­ry re­sis­tance to CAR T cell ther­a­py in ALL, the au­thors con­clud­ed.

“This mech­a­nism ap­pears to re­ly on two phas­es: an ini­tial re­sis­tance to death re­cep­tor-dri­ven killing, fol­lowed by an anti­gen-dri­ven, pro­gres­sive im­pair­ment in CAR-T cell func­tion. To­geth­er this leads to CAR T cell fail­ure that per­pet­u­ates dis­ease pro­gres­sion,” they wrote.

De­spite their abun­dant promise, the adop­tion of CAR-T ther­a­pies — No­var­tis’ Kym­ri­ah and Gilead’s Yescar­ta — has un­der­whelmed ini­tial ex­pec­ta­tions.

The up­take of Kym­ri­ah was plagued by man­u­fac­tur­ing prob­lems, and de­spite No­var­tis’ at­tempt to ex­pand its ca­pac­i­ty, sales con­tin­ue to dis­ap­point com­mer­cial­ly, giv­ing Yescar­ta an edge in the mar­ket. Mean­while, big side ef­fects — no­tably life-threat­en­ing episodes of cy­tokine re­lease syn­drome and neu­ro­tox­i­c­i­ty — as well as the ther­a­pies’ ex­pen­sive price tags have al­so lim­it­ed their use. Oth­er drug de­vel­op­ers have tak­en note of these con­straints and are de­vel­op­ing off-the-shelf CAR-T ther­a­pies, de­signed to smoothen man­u­fac­tur­ing com­plex­i­ties by us­ing healthy donor cells.

But the team at Penn cau­tioned that the prac­tice may not nec­es­sar­i­ly help the sub­set of pa­tients whose can­cer cells car­ry this pro­por­tion of un­fa­vor­able genes.

“A pos­si­ble im­pli­ca­tion of our ob­ser­va­tions is that the use of healthy donor (i.e. al­lo­gene­ic donor or “uni­ver­sal” donor) T cells as a sub­strate for CAR T cell man­u­fac­tur­ing may face the same bar­ri­ers as au­tol­o­gous prod­ucts,” the au­thors wrote. “Un­der­stand­ing how in­trin­sic and ac­quired T cell dys­func­tion co­op­er­ate to cause ther­a­peu­tic fail­ure will be crit­i­cal to the de­sign of the next gen­er­a­tion of cel­lu­lar ther­a­pies.”

The biggest ques­tions fac­ing gene ther­a­py, the XLMTM com­mu­ni­ty, and Astel­las af­ter fourth pa­tient death

After three patients died last year in an Astellas gene therapy trial, the company halted the study and began figuring out how to safely get the program back on track. They would, executives eventually explained, cut the dose by more than half and institute a battery of other measures to try to prevent the same thing from happening again.

Then tragically, Astellas announced this week that the first patient to receive the new regimen had died, just weeks after administration.

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What Will it Take to Re­al­ize the Promise and Po­ten­tial of Im­mune Cell Ther­a­pies?

What does it take to get to the finish line with a new cancer therapy – fast? With approvals in place and hundreds of immune cell therapy candidates in the pipeline, the global industry is poised to create a fundamental shift in cancer treatments towards precision medicine. At the same time, unique challenges associated with cell and process complexity present manufacturing bottlenecks that delay speed to market and heighten cost of goods sold (COGS) — these hurdles must be overcome to make precision treatments an option for every cancer patient. This series of articles highlights some of the key manufacturing challenges associated with the production of cell-based cancer therapies as well as the solutions needed to transcend them. Automation, process knowledge, scalability, and assured supply of high-quality starting material and reagents are all critical to realizing the full potential of CAR-based therapies and sustaining the momentum achieved in recent years. The articles will highlight leading-edge technologies that incorporate these features to integrate across workflows, accelerate timelines and reduce COGS – along with how these approaches are enabling the biopharmaceutical industry to cross the finish line faster with new treatment options for patients in need.

Lat­est news: It’s a no on uni­ver­sal boost­ers; Pa­tient death stuns gene ther­a­py field; In­side Tril­li­um’s $2.3B turn­around; 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.

Next week is shaping up to be a busy one, as our editor-in-chief John Carroll and managing editor Kyle Blankenship lead back-to-back discussions with a great group of experts to discuss the weekend news and trends. John will be spending 30 minutes with Jake Van Naarden, the CEO of Lilly Oncology, and Kyle has a brilliant panel lined up: Harvard’s Cigall Kadoch, Susan Galbraith, the new head of cancer R&D at AstraZeneca, Roy Baynes at Merck, and James Christensen at Mirati. Don’t miss out on the action — sign up here.

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President Biden and Pfizer CEO Albert Bourla (Patrick Semansky/AP Images)

Chaot­ic ad­comm sees Pfiz­er/BioN­Tech boost­ers re­ject­ed for gen­er­al pop­u­la­tion, but rec­om­mend­ed for old­er and high-risk pop­u­la­tions

With just days before President Joe Biden’s Covid-19 booster rollout is set to go into effect, an FDA advisory committee appeared on the verge of not recommending boosters for anyone in the US before a last-minute change of wording laid the groundwork for older adults to have access to a third dose.

The FDA’s adcomm on Vaccines and Related Biological Products (VRBPAC) roundly rejected Pfizer/BioNTech booster shots for all individuals older than 16 by a 16-2 vote Friday afternoon. Soon after, however, the agency posed committee members a new question limiting booster use to the 65-and-older population and individuals at high risk of disease due to occupational exposure or comorbidities.

As­traZeneca, Dai­ichi Sanky­o's ADC En­her­tu blows away Roche's Kad­cy­la in sec­ond-line ad­vanced breast can­cer

AstraZeneca and Japanese drugmaker Daiichi Sankyo think they’ve struck gold with their next-gen ADC drug Enhertu, which has shown some striking data in late-stage breast cancer trials and early solid tumor tests. Getting into earlier patients is now the goal, starting with Enhertu’s complete walkover of a Roche drug in second-line breast cancer revealed Saturday.

Enhertu cut the risk of disease progression or death by a whopping 72% (p=<0.0001) compared with Roche’s ADC Kadcyla in second-line unresectable and/or metastatic HER2-positive breast cancer patients who had previously undergone treatment with a Herceptin-chemo combo, according to interim data from the Phase III DESTINY-Breast03 head-to-head study presented at this weekend’s #ESMO21.

Merck Research Laboratories CMO Roy Baynes

Mer­ck­'s Keytru­da un­corks full da­ta on lat­est ad­ju­vant win — this time in melanoma — adding bricks to ear­ly can­cer wall

In recent months, the battle for PD-(L)1 dominance has spilled over into early cancer with Merck’s Keytruda and Bristol Myers Squibb’s Opdivo all alone on the front lines. Keytruda now has another shell in its bandolier, and it could spell a quick approval.

Keytruda cut the risk of relapse or death by 35% over placebo (p=0.00658) in high-risk, stage 2 melanoma patients who had previously undergone surgery to remove their tumors, according to full data from the Phase III KEYNOTE-716 presented Saturday at #ESMO21.

Mer­ck flesh­es out Keytru­da win in first-line cer­vi­cal can­cer, adding more fire­pow­er to its ear­ly can­cer push

Merck has worked hard to bring its I/O blockbuster Keytruda into earlier and earlier lines of therapy, and now the wonder drug appears poised to make a quick entry into early advanced cervical cancer.

A combination of Keytruda and chemotherapy with or without Roche’s Avastin cut the risk of death by 33% over chemo with or without Avastin (p=<0.001) in first-line patients with persistent, recurrent or metastatic cervical cancer, according to full data from the Phase III KEYNOTE-826 study presented Saturday at #ESMO21.

EQRx chairman Alexis Borisy and CEO Melanie Nallichieri

EQRx, CStone un­furl full lung can­cer da­ta for PD-L1 drug in what the part­ners are call­ing a first

As a self-stylized drug pricing disruptor, EQRx has high hopes for its lead PD-(L)1 to offer proof of concept for the entire business model. After touting a win back in May, the biotech is back with full data in lung cancer that could back up an approval.

Patients dosed with EQRx and CStone Pharmaceuticals’ sugemalimab posted median progression-free survival of 9 months compared with 5.8 months for patients given placebo (p=0.0026), according to full data from the Phase III GEMSTONE-301 study in Stage III non-small cell lung cancer set to be presented at this weekend’s #ESMO21.

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As­traZeneca touts Imfinzi im­munother­a­py com­bos for lung can­cer in push to dri­ve PD-L1 drug up­take

Facing the big dogs in the PD-(L)1 space, AstraZeneca has taken its own contender Imfinzi into blockbuster territory in its four years on the market but sees even bigger things for the drug. Combinations could be the key, and early results from a mid-stage test are adding some fuel to that strategy.

Imfinzi combined with one of two investigational immunotherapies — a CD73 antibody dubbed oleclumab or an Innate’s anti-NGK2a named monalizumab — topped Imfinzi alone in terms of overall response and progression-free survival in patients with stage III non-small cell lung cancer whose tumors had not worsened during concurrent chemoradiation, according to interim data from the Phase II COAST trial set to be presented at #ESMO21.