Fed Rate Cut Tailwind, Lilly’s Triple Agonist Delivers Big, Vaccine Policy Turmoil — This Week in Biotech #81
Plus Biohaven’s next-gen Trop2 data, Kymera’s STAT6 surge, AC Immune’s Parkinson’s signal, Mirum’s hepatitis delta bet, the CDC’s new Covid vaccine effectiveness data (Dec 5-11, 2025).
Hi and welcome to This Week in Biotech by Biotech Blueprint, edition 81, covering biotech & pharma news from December 5th to 11th, 2025.
📣 With the holidays approaching, This Week in Biotech will skip Dec 26 edition. Our final issue of the year drops next Friday, Dec 19, covering the biggest biotech developments of 2025, and we’ll be back Jan 2, 2026 with themes and companies to watch next year.
🌐 Visit our updated website, biotechblueprintconsulting.com, where we’re posting new visuals, reports, and details on our consulting work.
🎙️ Biotech Blueprint brings you weekly video updates on the latest biotech and pharma news, plus in-depth podcast interviews with industry leaders. You can find us on YouTube, Spotify, and Apple Podcasts.
In the latest episode, I sat down with NImmune founder and CEO Josep Bassaganya-Riera to talk about omilancor, the gut-restricted oral Inflammatory bowel disease drug now in Phase 3. We covered LANCL2 biology, their biomarker aimed at boosting response rates, and the TITAN-X platform that helps guide real development decisions. A really interesting look at how you build an oral immunology company in 2025. Below are the accompanying Substack article and podcast.
VIDEO SUMMARY
THIS WEEK’S KEY TAKEAWAYS 🔑
This week, the Federal Reserve delivered its second rate cut since September, shifting the economy into an easing cycle, which has historically been biotech’s strongest performance environment. Falling rates typically allow valuations to re-expand, reopen financing windows, and bring more investors back into the sector. After two cuts already and more likely in 2026, the headwind that suppressed the sector for nearly two years has flipped into a genuine tailwind.
On the public health front, the U.S. is sending mixed signals. A CDC analysis of nearly 100k children showed the updated Covid vaccine sharply reduced ER visits, especially in infants and toddlers, the age group with the highest hospitalization rates after seniors. Yet uptake remains stuck at 13%, and national guidance has pivoted from universal recommendation to “ask your doctor,” raising concern that evidence and policy are moving in opposite directions. At the same time, industry leaders are warning about the broader consequences of this skepticism. Moderna co-founder Noubar Afeyan warned that the U.S. is in danger of losing its lead in vaccine and mRNA science just as China accelerates its biotech ambitions.
Meanwhile, this week brought some of the most striking clinical data of the year. Eli Lilly’s triple agonist retatrutide produced bariatric surgery level weight loss and dramatic relief from knee osteoarthritis, a rare pairing in a single therapy. Biohaven reported a 52% response rate across tough solid tumors with its next generation Trop2 antibody-drug conjugate, including a clean pulmonary safety signal that has eluded first wave competitors. On the neuro front, AC Immune showed early but promising signs of disease stabilization in Parkinson’s through an alpha-synuclein vaccine approach. And in immunology, Kymera reported that its oral STAT6 degrader meaningfully reduced inflammation across skin and blood, with early improvements also seen in asthma and allergy symptoms.
Outside the headline catalysts, the week also brought mixed pipeline and business updates. Rezolute’s congenital hyperinsulinism drug failed phase 3, Roche’s oral estrogen receptor degrader modestly outperformed standard endocrine therapy in early breast cancer, and Mirum expanded its rare liver portfolio with the acquisition of Bluejay Therapeutics.
Continue reading for more stories.
BIOTECH/PHARMA NEWS 🧬
🔹 The Fed’s December 10 rate cut (its second since September) officially moves us into a real easing cycle, and historically that’s when biotech performs best. Over 45 years of data, the sector has delivered about +47% median annualized returns during periods of falling rates, compared with –5% during rate hikes. Lower rates make future earnings more valuable, reopen funding channels, and generally bring buyers back into the market. The impact usually unfolds over the next one to three quarters as valuations rise, the IPO window cracks open, and dealmaking picks up. With two cuts already in place and more expected into 2026, the macro drag that weighed on biotech from 2022 to 2024 has flipped into a meaningful tailwind.
🔹 A large CDC analysis of 98k children across nine states found that the 2024-25 Covid vaccine significantly reduced Covid-related ER and urgent care visits. For kids 9 months to 4 years old, the shot cut the risk by 76%. For those 5 to 17, the reduction was 56%, even in a population with plenty of prior infections and older vaccine doses. Infants remain the pediatric group with the highest Covid hospitalization rates outside seniors. Only about 13% of children received the updated vaccine, and that low uptake now intersects with a major policy shift: national guidance has moved from a universal recommendation to an “ask your doctor” approach under the new health leadership.
🔹 Moderna co-founder and chairman Noubar Afeyan warned that the U.S. is in “big danger” of losing its edge in vaccine and mRNA technology as NIH funding ebbs and political and public skepticism rises, just as China ramps biotech investment without similar resistance. Speaking to Bloomberg TV, he defended the safety of mRNA vaccines from Moderna, Pfizer, and BioNTech amid an ongoing FDA review of potential vaccine-related deaths, pointing to extensive data and estimates that COVID shots prevented nearly 20 million deaths globally in their first year, including more than one million in the U.S., and urging regulators to focus on evidence rather than sentiment. Afeyan’s comments come as Moderna’s shares are down 32% over the past year on falling COVID vaccine sales and over reliance on a shrinking franchise.
🔹 Mirum Pharmaceuticals will acquire privately held Bluejay Therapeutics for $250M in cash, $370M in stock and up to $200M in sales milestones, adding full global rights to brelovitug, a fully human monoclonal antibody in phase 3 for chronic hepatitis delta virus, the most severe form of viral hepatitis with no approved U.S. treatments and about 230k patients across the U.S. and Europe. Brelovitug, which carries Breakthrough Therapy, PRIME and Orphan designations, has shown strong antiviral activity and liver enzyme improvements in phase 2 and could support a biologics license application and potential launch in 2027. Mirum is funding part of the deal via a $200M private placement, effectively levering its existing rare liver commercial footprint (LIVMARLI, CHOLBAM, CTEXLI) into a second major franchise.
🔹 On Friday (12/5), ACIP voted 8-3 to end the universal newborn hepatitis B dose for infants born to mothers who test negative, replacing it with “shared decision-making,” while maintaining the birth dose for infants of mothers who are positive or whose status is unknown. The move reverses a policy credited with a 99% drop in pediatric hepatitis B since 1991 and drew immediate pushback from medical groups concerned infections will rise. After two days of procedural confusion and rewritten ballots, the recommendation now goes to acting CDC director Jim O’Neill, who can accept or reject it. Sen. Bill Cassidy, a hepatologist, has already urged him not to adopt the change.
CLINICAL TRIAL UPDATES 📊
🔹 Eli Lilly’s “triple agonist” retatrutide just posted the kind of phase 3 results that reshape an entire category: in adults with obesity and knee osteoarthritis, the highest dose drove 29% weight loss among adherent patients (71 lbs on average) and even 24% weight loss when counting dropouts, numbers that edge into bariatric-surgery territory. Knee pain also fell 75%, and more than 1 in 8 patients ended the trial completely pain-free, a meaningful signal in a population where cartilage loss normally means a slow march toward joint replacement. The usual incretin side effects (nausea, diarrhea, vomiting) were common but mostly manageable. Discontinuations were higher at the top dose, with some patients stopping due to excessive weight loss.
🔹 Biohaven’s Trop2-targeting antibody-drug conjugate BHV-1510, paired with Regeneron’s anti-PD-1 antibody Libtayo, delivered eye catching phase 1 signals in heavily pretreated solid tumors: among 23 patients, the combo hit a 52% confirmed response rate overall, including 60% in non-small cell lung cancer, 100% in endometrial cancer (one complete response), and 50% in urothelial cancer, with most patients having already failed prior PD-1/PD-L1 therapy. The safety profile looks meaningfully differentiated from first wave Trop2 antibody-drug conjugates, with low rates of neutropenia, diarrhea, and alopecia, and importantly, no interstitial lung disease so far, though oral mucositis and stomatitis remain a class tax and drove most higher-grade events.
🔹 Rezolute’s phase 3 sunRIZE trial in congenital hyperinsulinism failed to meet its primary and key secondary endpoints, with the top ersodetug dose showing a 45% reduction in weekly hypoglycemia events versus a 40% improvement on placebo and no statistically significant benefit on continuous glucose monitoring time-in-hypoglycemia. Safety was generally acceptable aside from two hypersensitivity reactions, but the efficacy signal was too weak to support the program, leading the company to halt development in this indication while still planning an FDA discussion under its Breakthrough Therapy designation. Shares collapsed nearly 90%, and partner Xoma was hit as well on the loss of future royalty expectations.
🔹 AC Immune reported interim phase 2 data for its alpha-synuclein-targeting immunotherapy ACI-7104.056 in early Parkinson’s disease, showing the shot generated strong antibody responses in 100% of treated patients and produced signs of stabilized disease across multiple biomarker and clinical measures after 12-18 months of treatment. Markers tied to pathology and neurodegeneration (cerebrospinal fluid alpha-synuclein and neurofilament light chain) remained steady in the treatment arm but worsened on placebo, while motor scores also showed a trend toward stabilization. Safety looked clean, with no serious adverse events and mostly mild injection site reactions. The company now plans to meet regulators to explore accelerating development ahead of final part 1 data in mid-2026.
🔹 Roche reported additional phase 3 data showing its oral selective estrogen receptor degrader giredestrant cut the risk of invasive disease recurrence or death by 30% in more than 4k patients with early stage, estrogen receptor positive breast cancer, an area where up to a third of patients eventually relapse on today’s endocrine therapies. Three year invasive disease free survival reached 92.4% on giredestrant versus 89.6% on standard treatment, with a favorable safety profile and fewer discontinuations. The trial positions giredestrant as the first oral endocrine therapy in decades to outperform standard care in the adjuvant setting, though questions remain about how it will be used alongside CDK4/6 inhibitors.
🔹 Kymera’s shares jumped 50% after early phase 1b data for KT-621 showed strong activity in moderate to severe eczema. The oral STAT6 degrader reduced STAT6 levels by more than 90% in both blood and skin lesions, and delivered meaningful clinical improvements. About a 63% drop in Eczema Area and Severity Index scores and a 40% reduction in itch after four weeks with no serious or treatment-related safety issues. Patients with asthma and allergic rhinitis also saw early benefits, hinting at broader potential across type 2 inflammatory diseases. Phase 2b eczema data are expected in 2027, with an asthma trial starting next year.
Have a great rest of your week and thanks for reading Biotech Blueprint!
