
Scientists have detected the largest black hole merger yet. What it is and why it matters
On Nov. 23, 2023, waves from a colossal merger of two black holes reached Earth and were picked up by the LIGO-Virgo-KAGRA Collaboration, a group that detects these sort of mergers through gravitational waves.
And these black holes were chunky, coming in at 100 and 140 times the mass of the sun.
But the final merger produced something even more impressive: another black hole that is more than 225 times the mass of the sun, astronomers revealed today.
Astronomers are excited about this merger because it's unusual. Most of these kinds of mergers detected thus far through gravitational waves have been between 10 and 40 times the sun, said Sophie Bini, a postdoctoral researcher at Caltech who is part of the group.
WATCH | Scientists detect gravitational waves for 1st time:
Scientists detect gravitational waves for 1st time
9 years ago
Duration 0:51
"We detected the first gravitational wave 10 years ago, and since then, we have already found more than 300 events. So it's really an exciting [time]," Bini said. "But this event in particular is very interesting because it's the most massive one."
Gravitational waves are ripples in space-time that can only be detected by extremely sensitive instruments, like the ones from the collaboration, which are located across the United States, Japan and Italy.
The first gravitational wave was detected in 2015 and announced by astronomers in 2016.
The other interesting discovery of this detection — called GW231123 — is that the pair appear to have been spinning extremely quickly.
"The black holes appear to be spinning very rapidly — near the limit allowed by [Albert] Einstein's theory of general relativity," Charlie Hoy at the University of Portsmouth said in a statement. "That makes the signal difficult to model and interpret. It's an excellent case study for pushing forward the development of our theoretical tools."
Understanding black holes
Not all black holes are created equal.
There are supermassive black holes that can be tens of thousands to billions of times the sun's mass and lie at the centre of galaxies. The Milky Way, for example, has a black hole at its centre, called Sagittarius A* — or Sgr A* — that is roughly four million times the mass of the sun.
Then there are stellar-mass black holes, which can be from a few times the mass of the sun to tens of times the mass. Or, some argue, a hundred of times its mass. These form when a massive star runs out of fuel and explodes in a spectacular fashion, an event called a supernova.
But then there are those that lie somewhere in between the two, called intermediate black holes. Finding these in-betweens has proved difficult for astronomers. This new merger lies within what astronomers call the "mass gap" between stellar-mass and supermassive black holes.
Gobbling up stars
It's not quite clear why these two black holes were so much heavier than what astronomers have previously detected. One theory is that each of the pair itself was the result of two black holes merging.
But that's not the only theory.
Priya Natarajan, professor of physics and the chair of astronomy at Yale University, studies supermassive black holes. Though these two black holes are piddly compared to the ones she studies, she says she is excited about the recent detection.
"I think this is super exciting for two reasons. First is the heaviness of the individual black holes before they actually merge," said Natarajan, who was not involved with the findings. "So the fact is that, you know, normal stellar processes that give you these stellar-mass remnant black holes, it's pretty hard to imagine, like, getting to 100 and 140 in one go."
But she has another theory on how these two unusual black holes could have formed.
In 2014, she co-authored a paper that suggested black holes could grow rapidly in the early universe by first going supernova and then by gobbling up stars in a nascent star cluster, à la Pac-Man. More gas means larger black holes. But she says in 2021, she realized this could happen later in the more recent universe, as well.
"The only thing that is different is there's not as much gas," she said. "So I actually showed that if there's not that much gas, you could start with something that's one or ten times the mass of the sun. It could maybe reach 100.… If there's little more gas, it could be 1,000."
So this new finding could open up a new avenue for cosmologists like herself to explore.
The next thing she'd like to see is a better way to locate these mergers. For the recent detection, there is an estimate that it occurred anywhere from two to 13 billion light years away.
Now, why are these findings important?
It's about the human connection with the universe, Natarajan said.
"I think from the moment that as Neanderthals we stood upright and we were able to look at the night sky, we were fascinated with the regularity of the night sky, as well as the sort of cosmic drama that's going on, right? You see stars exploding, you see eclipses, you see night and day, you see seasonal changes. And I think it speaks to a fundamental curiosity that we as humans have," she said.
"I think that knowing our place in the universe is a question that's deeply fundamental to us. And it always has been."
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Globe and Mail
3 hours ago
- Globe and Mail
Sarepta Therapeutics Provides Clarifying Statement on ELEVIDYS
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As reported yesterday by Naomi Kresge at Bloomberg News: Roche Holding AG says the recent death of a patient in Brazil who had been treated with gene therapy Elevidys for Duchenne muscular dystrophy is unrelated to the treatment. * The boy wasn't a clinical trial participant; reporting physician assessed his death as being unrelated to the gene therapy, Roche says in statement * Death was reported to health authorities * Roche, which markets Sarepta's Duchenne treatment Elevidys outside the US, declines to comment on the boy's age or details of the case Sarepta reported this event to FDA on June 18, 2025, via the FDA's postmarketing electronic database, FAERS. At Sarepta, patient safety and well-being are always our top priority. We are committed to upholding the highest safety standards for all of our therapies, and do so in accordance with applicable law and commitment to full regulatory transparency. ELEVIDYS is the only approved gene therapy for families and children devastated by Duchenne, a rare, progressive and ultimately fatal disease. We remain committed to working closely with the FDA to ensure that all decisions are grounded in science and the best interests of patients, considering the compelling need of these families to access disease-modifying therapy. About ELEVIDYS (delandistrogene moxeparvovec-rokl) ELEVIDYS (delandistrogene moxeparvovec-rokl) is a single-dose, adeno-associated virus (AAV)-based gene transfer therapy for intravenous infusion designed to address the underlying genetic cause of Duchenne muscular dystrophy – mutations or changes in the DMD gene that result in the lack of dystrophin protein – through the delivery of a transgene that codes for the targeted production of ELEVIDYS micro-dystrophin in skeletal muscle. ELEVIDYS is indicated for the treatment of Duchenne muscular dystrophy (DMD) in individuals at least 4 years of age. For patients who are ambulatory and have a confirmed mutation in the DMD gene For patients who are non-ambulatory and have a confirmed mutation in the DMD gene. The DMD indication in non-ambulatory patients is approved under accelerated approval based on expression of ELEVIDYS micro-dystrophin in skeletal muscle. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial(s). IMPORTANT SAFETY INFORMATION CONTRAINDICATION: ELEVIDYS is contraindicated in patients with any deletion in exon 8 and/or exon 9 in the DMD gene. WARNINGS AND PRECAUTIONS: Infusion-related Reactions: Infusion-related reactions, including hypersensitivity reactions and anaphylaxis, have occurred during or up to several hours following ELEVIDYS administration. Closely monitor patients during administration and for at least 3 hours after the end of infusion. 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Limited data are available for ELEVIDYS treatment in patients with mutations in the DMD gene in exons 1 to 17 and/or exons 59 to 71. Patients with deletions in these regions may be at risk for a severe immune-mediated myositis reaction. Advise patients to contact a physician immediately if they experience any unexplained increased muscle pain, tenderness, or weakness, including dysphagia, dyspnea, or hypophonia, as these may be symptoms of myositis. Consider additional immunomodulatory treatment (immunosuppressants [e.g., calcineurin-inhibitor] in addition to corticosteroids) based on patient's clinical presentation and medical history if these symptoms occur. Myocarditis: Acute serious myocarditis and troponin-I elevations have been observed following ELEVIDYS infusion in clinical trials. If a patient experiences myocarditis, those with pre-existing left ventricle ejection fraction (LVEF) impairment may be at higher risk of adverse outcomes. Monitor troponin-I before ELEVIDYS infusion and weekly for the first month following infusion and continue monitoring if clinically indicated. More frequent monitoring may be warranted in the presence of cardiac symptoms, such as chest pain or shortness of breath. Advise patients to contact a physician immediately if they experience cardiac symptoms. Preexisting Immunity against AAVrh74: In AAV-vector based gene therapies, preexisting anti-AAV antibodies may impede transgene expression at desired therapeutic levels. Following treatment with ELEVIDYS, all patients developed anti-AAVrh74 antibodies. Perform baseline testing for presence of anti-AAVrh74 total binding antibodies prior to ELEVIDYS administration. ELEVIDYS administration is not recommended in patients with elevated anti-AAVrh74 total binding antibody titers greater than or equal to 1:400. Adverse Reactions: The most common adverse reactions (incidence ≥5%) reported in clinical studies were vomiting, nausea, liver injury, pyrexia, and thrombocytopenia. Report negative side effects of prescription drugs to the FDA. Visit or call 1-800-FDA-1088. You may also report side effects to Sarepta Therapeutics at 1-888-SAREPTA (1-888-727-3782). For further information, please see the full Prescribing Information. About Sarepta Therapeutics Sarepta is on an urgent mission: engineer precision genetic medicine for rare diseases that devastate lives and cut futures short. We hold a leadership position in Duchenne muscular dystrophy (Duchenne) and are building a robust portfolio of programs across muscle, central nervous system, and cardiac diseases. For more information, please visit or follow us on LinkedIn, X, Instagram and Facebook. Forward-Looking Statements This statement contains 'forward-looking statements.' Any statements that are not statements of historical fact may be deemed to be forward-looking statements. Words such as 'believe,' 'anticipate,' 'plan,' 'expect,' 'will,' 'may,' 'intend,' 'prepare,' 'look,' 'potential,' 'possible' and similar expressions are intended to identify forward-looking statements. These forward-looking statements include, without limitation, statements relating to our future operations, research and development programs, clinical trials and ELEVIDYS. Actual results could materially differ from those stated or implied by these forward-looking statements as a result of such risks and uncertainties. Known risk factors include the following: our products or product candidates may be perceived as insufficiently effective, unsafe or may result in unforeseen adverse events; our products or product candidates may cause undesirable side effects that result in significant negative consequences following any marketing approval; the possible impact of regulations and regulatory decisions by the FDA and other regulatory agencies on our business; and those risks identified under the heading 'Risk Factors' in our most recent Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission (SEC) as well as other SEC filings made by the Company, which you are encouraged to review. Any of the foregoing risks could materially and adversely affect the Company's business, results of operations and the trading price of Sarepta's common stock. For a detailed description of risks and uncertainties Sarepta faces, you are encouraged to review the SEC filings made by Sarepta. We caution investors not to place considerable reliance on the forward-looking statements contained herein. Sarepta does not undertake any obligation to publicly update its forward-looking statements based on events or circumstances after the date hereof, except as required by law. Source: Sarepta Therapeutics, Inc.


Globe and Mail
5 hours ago
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Amyotrophic Lateral Sclerosis Pipeline Insight 2025: 75+ Companies Accelerating Innovation Across Genetic and Neuroinflammatory Targets
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ALS is often classified into sporadic (the most common form) and familial types, with the latter being linked to genetic mutations. Although the exact cause of ALS is unknown in most cases, environmental and genetic factors are believed to contribute to its development. Currently, there is no cure for ALS, but several treatment options aim to slow disease progression and manage symptoms. FDA-approved drugs like riluzole and edaravone offer modest benefits in extending survival or preserving function. Ongoing research is focused on gene therapies, neuroprotective agents, and immune-targeting approaches to better address the underlying mechanisms of the disease and improve patient outcomes. Find out more about amyotrophic lateral sclerosis medication at Amyotrophic Lateral Sclerosis Treatment Analysis: Drug Profile MN-166: MediciNova MN-166 is an orally administered small molecule glial attenuator that reduces neuroinflammation by suppressing pro-inflammatory cytokines such as IL-1β, TNF-α, and IL-6, while potentially increasing the anti-inflammatory cytokine IL-10. It also functions as a toll-like receptor 4 (TLR4) antagonist, contributing further to its anti-inflammatory effects. MN-166 is currently in Phase II/III clinical trials for the treatment of ALS. RNS60: Revalesio RNS60 is designed to offer disease-modifying and potentially regenerative effects in neurological disorders. It works by activating signaling pathways that enhance mitochondrial function and reduce inflammation, offering neuroprotection and immune modulation. The FDA has granted RNS60 both Orphan Drug and Fast Track status for ALS. It is currently in Phase II clinical trials. VM202: Helixmith VM202 is a gene therapy aimed at tissue regeneration by promoting the production of hepatocyte growth factor (HGF) at the site of injection along peripheral nerves. HGF supports nerve protection, neuron growth, and muscle atrophy prevention. The FDA has granted VM202 Orphan Drug and Fast Track designations. It is being evaluated in Phase II trials for ALS treatment. Learn more about the novel and emerging amyotrophic lateral sclerosis pipeline therapies. By Product Type • Mono • Combination • Mono/Combination. By Stage • Late-stage products (Phase III) • Mid-stage products (Phase II) • Early-stage product (Phase I) along with the details of • Pre-clinical and Discovery stage candidates • Discontinued & Inactive candidates By Route of Administration • Intravenous • Subcutaneous • Oral • Intramuscular By Molecule Type • Monoclonal antibody • Small molecule • Peptide Scope of the Amyotrophic Lateral Sclerosis Pipeline Report • Coverage: Global • Key Amyotrophic Lateral Sclerosis Companies: Ionis Pharmaceuticals, 1ST Biotherapeutics, Scholar Rock, Revalesio, QurAlis Corporation, Sanofi, MediciNova, Helixmith, Verge Genomics, UCB, and others. • Key Amyotrophic Lateral Sclerosis Pipeline Therapies: ION363, FB418, SRK-015, RNS60, QRL-201, SAR443820, MN-166, VM202, VRG-50635, Zilucoplan, and others. Explore detailed insights on drugs used in the treatment of amyotrophic lateral sclerosis here. Table of Contents 1. Introduction 2. Executive Summary 3. Amyotrophic Lateral Sclerosis Pipeline: Overview 4. Analytical Perspective In-depth Commercial Assessment 5. Amyotrophic Lateral Sclerosis Pipeline Therapeutics 6. Amyotrophic Lateral Sclerosis Pipeline: Late-Stage Products (Phase III) 7. Amyotrophic Lateral Sclerosis Pipeline: Mid-Stage Products (Phase II) 8. Amyotrophic Lateral Sclerosis Pipeline: Early Stage Products (Phase I) 9. Therapeutic Assessment 10. Inactive Products 11. Company-University Collaborations (Licensing/Partnering) Analysis 12. Key Companies 13. Key Products 14. Unmet Needs 15. Market Drivers and Barriers 16. Future Perspectives and Conclusion 17. Analyst Views 18. Appendix About DelveInsight DelveInsight is a leading Business Consultant and Market Research firm focused exclusively on life sciences. It supports Pharma companies by providing comprehensive end-to-end solutions to improve their performance. Get hassle-free access to all the healthcare and pharma market research reports through our subscription-based platform, PharmDelve. Media Contact Company Name: DelveInsight Contact Person: Jatin Vimal Email: Send Email Phone: +14699457679 Address: 304 S. Jones Blvd #2432 City: Las Vegas State: Nevada Country: United States Website:


CBC
5 hours ago
- CBC
Trump's NASA cuts will 'compromise human safety,' hundreds of employees say in letter
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