Fetal and neonatal alloimmune thrombocytopenia

– RLYB212 Phase 2 PK Results Did Not Achieve Target Concentrations, Including Minimum Target Concentration Required for Efficacy – – RLYB116 Confirmatory PK/PD Study to Initiate in 2Q 2025, with Data in 2H 2025 – NEW HAVEN, CT, USA I April 08, 2025 I Rallybio Corporation (Nasdaq: RLYB), a clinical-stage biotechnology company translating scientific advances into transformative therapies for patients with devastating rare diseases, today announced the discontinuation of the RLYB212 program for the prevention of fetal and neonatal alloimmune thrombocytopenia (FNAIT). The Company’s decision to discontinue RLYB212 development was based on pharmacokinetic (PK) data from the Phase 2 clinical trial demonstrating the inability of the RLYB212 dose regimen to achieve predicted target concentrations, as well as the minimum target concentration required for efficacy. Rallybio remains focused on advancing RLYB116, a once-weekly low volume C5 inhibitor for the treatment of complement-driven diseases, as well as its emerging preclinical programs. “We are disappointed by the PK results of the RLYB212 Phase 2 trial,” said Stephen Uden, M.D., Chief Executive Officer of Rallybio. “Given that the results significantly deviated from the predicted range and the absence of empiric data to further inform dose adjustment, the risk/benefit no longer supports continued dosing, and we will discontinue RLYB212 development. We are grateful to the participants, investigators, and study staff for their partnership and dedication to this program.” Dr. Uden continued, “Rallybio remains steadfast in our mission to develop transformative therapies. We are focused on creating shareholder value by advancing our portfolio of potentially best-in-class assets for patients with rare diseases, which includes RLYB116 and REV102, an ENPP1 inhibitor for patients with hypophosphatasia, as well as RLYB332, a long-acting matriptase-2 antibody for diseases of iron overload.” RLYB212 Phase 2 Trial The single-arm Phase 2 dose confirmation trial was designed to assess the PK and safety of RLYB212 in pregnant women at higher risk for HPA-1a alloimmunization and FNAIT. Secondary objectives included the assessment of pregnancy and neonatal/infant outcomes, and the occurrence of emergent HPA-1a alloimmunization. Second trimester PK results from the sentinel participant demonstrated an inability of RLYB212 to achieve predicted target concentrations of 6 ng/mL to 10 ng/mL, as well as the minimum target concentration required for efficacy of 3 ng/mL, with values near or below the assay’s lower limit of quantitation. Dose adjustment is not deemed feasible given that PK levels are meaningfully outside the predicted range and the absence of empiric data to inform an adjustment. It is hypothesized that HPA-1a antigen expression on the placenta may be impacting plasma concentrations of RLYB212. No further enrollment in the trial is planned and all screening of participants has been stopped. The Company will continue safety follow-up of the sentinel participant as specified in the clinical trial protocol. Promising Rare Disease Pipeline to Deliver Data in 2H 2025 RLYB116 Program Rallybio remains on track to initiate dosing in the RLYB116 confirmatory clinical pharmacokinetic/ pharmacodynamic (PK/PD) study in the second quarter of 2025, with data readouts from Cohorts 1 and 2 expected in the third and fourth quarter of 2025, respectively. The study is expected to demonstrate complete and sustained complement inhibition with improved tolerability of RLYB116. RLYB116 is a novel antibody mimetic fusion protein designed to inhibit C5 and to provide a once-weekly, small volume, subcutaneously injected therapy to meet patient demand for a convenient, self-administered at-home solution. RLYB116 has the potential to address significant unmet need for patients across a number of complement mediated diseases, including paroxysmal nocturnal hemoglobinuria (PNH), antiphospholipid syndrome (APS), and generalized myasthenia gravis (gMG), which together represent a commercial opportunity of more than $6 billion. Importantly, this strategic focus on complement-mediated diseases presents a unique opportunity for Rallybio to utilize its team’s deep domain experience in successfully designing, developing, and delivering complement inhibitors for patients with rare diseases. Preclinical Programs REV102, an ENPP1 inhibitor for the treatment of patients with HPP under development through a joint venture with Recursion Pharmaceuticals, entered investigational new drug application (IND)-enabling studies in the first quarter of 2025 to support the initiation of a Phase 1 study in 2026. Data evaluating REV102 in a preclinical model of later-onset HPP is expected in the second half of 2025. Rallybio’s portfolio also includes RLYB332, a long-acting, monoclonal anti-matriptase-2 antibody that has the potential to be a best-in-class treatment for diseases of iron overload. Preclinical data has demonstrated superior impact on PD parameters relative to comparator molecules, including on serum iron, unsaturated iron binding capacity (UIBC), and transferrin saturation (TSAT). The Company is preparing plans for future development of RLYB332. About Rallybio Rallybio (NASDAQ: RLYB) is a clinical-stage biotechnology company with a mission to develop and commercialize life-transforming therapies for patients with severe and rare diseases. Rallybio has built a pipeline of promising product candidates aimed at addressing diseases with unmet medical need in areas of complement dysregulation, hematology, and metabolic disorders. The Company’s lead program, RLYB116, is a differentiated C5 inhibitor with the potential to treat diseases of complement dysregulation. Rallybio also has two programs in preclinical development, including REV102, an ENPP1 inhibitor for the treatment of patients with hypophosphatasia (HPP), and RLYB332, a long-acting matriptase-2 antibody for the treatment of diseases of iron overload. Rallybio is headquartered in New Haven, Connecticut. For more information, please visit www.rallybio.com and follow us on LinkedIn and Twitter . SOURCE: Rallybio

Shares in Rallybio fell 50% to 21 cents in premarket trading. \n Rallybio’s lead program has crashed out. Racing toward a $1.6 billion market, the biotech stopped work on RLYB212 in a rare maternal immune disorder in response to phase 2 data.RLYB212, an anti-HPA-1a antibody, was in phase 2 development for the prevention of fetal and neonatal alloimmune thrombocytopenia (FNAIT). The condition occurs when a mother’s immune system identifies her baby’s platelets as foreign and mounts an attack. No drugs are approved to prevent or treat FNAIT, which Rallybio has valued as a $1.6 billion opportunity.Rallybio ended its pursuit of the opportunity on Tuesday, sending the company\'s struggling shares down 50% in pre-market trading to 21 cents from a Monday closing price of 42 cents.The biotech stopped development of RLYB212 after concentrations of the drug in the first person enrolled in the phase 2 trial fell short of the target range.Researchers predicted target concentrations of 6 ng/mL to 10 ng/mL in the second trimester. Rallybio set 3 ng/mL as the minimum concentration required for efficacy. When the data came in, the biotech found the values were near or below the assay’s lower limit of quantitation.  Rallybio CEO Steve Uden, M.D., discussed the prospect of concentrations missing the bottom end of the range at a TD Cowen event last month. In that scenario, the data would inform changes to the dose to ensure Rallybio hit the range in the next cohort, the CEO said. However, the candidate missed the mark by such a wide margin that Rallybio opted against trying to adjust the dose on feasibility grounds.The biotech’s current hypothesis is that HPA-1a antigen expression on the placenta may be impacting plasma concentrations of RLYB212. Whatever the reason, the result is that Rallybio has shifted its focus to its once-weekly low-volume C5 inhibitor RLYB116 and its preclinical programs. Uden and other people at Rallybio know the C5 space well from their time at Alexion.Rallybio is working to start dosing RLYB116 in a confirmatory pharmacokinetic/pharmacodynamic study in the second quarter. The biotech is aiming to share results from the first two cohorts in the third and fourth quarters. Rallybio wants to see complete and sustained complement inhibition with improved tolerability to support its positioning of RLYB116 as a drug that patients can self-administer at home. 

New compelling results demonstrate 18 months of both sustained reduction in immunoglobulin G antibodies and sustained improvement in gMG symptoms in pivotal Vivacity-MG3 study and open-label extension phase Up to 128 weeks and 180 patient years of follow-up in the open-label extensiona confirm a safety profile consistent with the Phase 3 Vivacity-MG3 study 45% of the patients receiving steroids at open-label extension baseline were able to decrease or discontinue their steroid use Additionally, the nipocalimab plus standard of care (SOC) group demonstrated four times greater odds of improving and maintaining the strength and function of different muscle groups as measured by QMGb response versus placebo plus SOC in the 24-week double blind phase of the study SPRING HOUSE, Pa., April 8, 2025 /PRNewswire/ -- Johnson & Johnson (NYSE: JNJ) today announced results from additional analyses of the Phase 3 Vivacity-MG3 double-blind study and the ongoing open-label extensiona (OLE), evaluating the long-term efficacy and safety of investigational nipocalimab in a broad population of antibody-positive (anti-AChR+, anti-MuSK+, anti-LRP4+) adults with generalized myasthenia gravis (gMG).1,2 Patients treated with nipocalimab plus standard of care (SOC) maintained improvements in their MG-ADLc and QMGb scores over 84 weeks with sustained reductions in total immunoglobulin G (IgG).1 These data are included in a presentation (Session 7 #022) and are among 12 abstracts that Johnson & Johnson will present at the American Academy of Neurology (AAN) 2025 Meeting in San Diego, California, which includes an oral presentation on QMG score improvements from the double-blind phase of the Phase 3 Vivacity-MG3 study. "The sustained disease control seen over 84 weeks for nipocalimab is a key result given the chronic course of generalized MG and the significant burden on people living with this condition," said Constantine Farmakidis M.D., Associate Professor of Neurology at University of Kansas Medical Centerd. "Overall, I am encouraged by these results that show improvement in disease control as measured by the MG-ADL and QMG scores across a broad population seropositive for AChR, MuSK, or LRP4 autoantibodies." Nipocalimab demonstrated a mean change in MG-ADL of -5.64 (p<0.001) from the double-blind baseline after 60 weeks in the OLE for study participants receiving nipocalimab and SOC, and -6.01 (p<0.001) mean change for study participants who transitioned from placebo and SOC to nipocalimab and SOC.1 In the antibody-positive population, 45% of patients receiving steroids at the OLE baseline were able to decrease or discontinue steroids at the time of this data cut by more than half of the baseline dose.1 Among these patients, the mean dose of prednisone decreased from 23 to 10 mg per day.1 Nipocalimab had a consistent and tolerable safety profile throughout the OLE phase.1 Additional findings from the Phase 3 Vivacity-MG3 double-blind study indicate that patients treated with nipocalimab plus SOC achieved statistically significant improvements in their QMG score by -4.9 versus placebo plus SOC (p<0.001) over weeks 22 and 24.2 Patients in the nipocalimab plus SOC treatment group were four times more likely to sustain symptom improvement at 20 weeks compared to the placebo plus SOC group, as measured by a three or greater point improvement on the QMG score.2 Results show significantly more patients treated with nipocalimab (36.4%,) versus placebo (10.5%, p<0.001) spent greater than 75% of study duration demonstrating improvements in the QMG score.2 A reduction of more than three points in the QMG score indicates a decrease in the severity of the patient's symptoms as a result of improvements in muscle strength, allowing patients to carry out important daily activities such as swallowing and chewing.3,4 "People living with generalized MG around the world endure daily challenges, such as difficulties swallowing, impaired speech and muscle weakness. They deserve additional, effective treatment options that help address these challenges and provide sustained disease control and stability over time," said Katie Abouzahr, M.D., Vice President, Autoantibody Portfolio and Maternal Fetal Immunology Disease Area Leader, Johnson & Johnson Innovative Medicine. "These positive data underscore our commitment to helping develop potential innovative therapeutic options for patients living with autoantibody diseases, including gMG." Editor's notes: ABOUT GENERALIZED MYASTHENIA GRAVIS (gMG) Myasthenia gravis (MG) is an autoantibody disease in which the immune system mistakenly makes antibodies (e.g., anti-acetylcholine receptor [AChR], anti-muscle-specific tyrosine kinase [MuSK] or anti-low density lipoprotein-related protein 4 [LRP4]), which target proteins at the neuromuscular junction, and can block or disrupt normal signaling from nerves to muscles, thus impairing or preventing muscle contraction.5,6,7 The disease impacts an estimated 700,000 people worldwide.5 The disease affects both men and women and occurs across all ages, racial and ethnic groups, but most frequently starts in young women and older men.8 Roughly 50 percent of individuals diagnosed with MG are women, and about one in five of those women are of child-bearing potential.9,10,11 Approximately 10 to 15% of new cases of MG are diagnosed in adolescents (12 – 17 years of age).12,13,14 Among juvenile MG patients, girls are affected more often than boys with over 65% of pediatric MG cases in the U.S. diagnosed in girls.15,16,17 Initial disease manifestations are usually ocular, but 85 percent of MG patients experience additional advancements to the disease manifestations – referred to as generalized myasthenia gravis (gMG). This is characterized by severe muscle weakness of the skeletal muscles and difficulties in speech and swallowing.18,19,20,21,22 Approximately 100,000 individuals in the U.S. are living with gMG.23 Vulnerable gMG populations, such as pediatric patients, have more limited therapeutic options.24 Currently, SOC treatments for adolescents with gMG are extrapolated from adult trials.14 Other than symptomatic treatments, there are no approved FcRn blockers for adolescents with gMG in the United States.14 ABOUT THE PHASE 3 VIVACITY-MG3 STUDY The Phase 3 Vivacity-MG3 study (NCT04951622) was specifically designed to measure sustained efficacy and safety with consistent dosing in this unpredictable chronic condition where unmet need remains high. Antibody positive or negative adult gMG patients with insufficient response (MG-ADL ≥6) to ongoing SOC therapy were identified and 199 patients, 153 of whom were antibody positive, enrolled in the 24-week double-blind placebo-controlled trial.25,26 Randomization was 1:1, nipocalimab plus current SOC (30 mg/kg IV loading dose followed by 15 mg/kg every two weeks) or placebo plus current SOC.25 Baseline demographics were balanced across arms (77 nipocalimab, 76 placebo).25 The primary endpoint of the study was mean change in MG-ADLb score from baseline over Weeks 22, 23 and 24 in antibody positive patients. A key secondary endpoint included change in QMG score. Long-term safety and efficacy were further assessed in an ongoing open-label extension (OLE) phase.26 ABOUT NIPOCALIMAB Nipocalimab is an investigational monoclonal antibody, designed to bind with high affinity to block FcRn and reduce levels of circulating immunoglobulin G (IgG) antibodies potentially without impact on other immune functions. This includes autoantibodies and alloantibodies that underlie multiple conditions across three key segments in the autoantibody space including Rare Autoantibody diseases, Maternal Fetal diseases mediated by maternal alloantibodies and Rheumatic diseases.26,27,28,29,30,31,32,33,34 Blockade of IgG binding to FcRn in the placenta is also believed to limit transplacental transfer of maternal alloantibodies to the fetus.35,36 The U.S. FDA and EMA have granted several key designations to nipocalimab including: U.S. FDA Fast Track designation in hemolytic disease of the fetus and newborn (HDFN) and warm autoimmune hemolytic anemia (wAIHA) in July 2019, gMG in December 2021 and fetal neonatal alloimmune thrombocytopenia (FNAIT) in March 2024 and Sjögren's disease (SjD) in March 2025 U.S. FDA Orphan drug status for wAIHA in December 2019, HDFN in June 2020, gMG in February 2021, chronic inflammatory demyelinating polyneuropathy (CIDP) in October 2021 and FNAIT in December 2023 U.S. FDA Breakthrough Therapy designation for HDFN in February 2024 and for Sjögren's disease in November 2024 U.S. FDA granted Priority Review in gMG in Q4 2024 EU EMA Orphan medicinal product designation for HDFN in October 2019 ABOUT JOHNSON & JOHNSON At Johnson & Johnson, we believe health is everything. Our strength in healthcare innovation empowers us to build a world where complex diseases are prevented, treated, and cured, where treatments are smarter and less invasive, and solutions are personal. Through our expertise in Innovative Medicine and MedTech, we are uniquely positioned to innovate across the full spectrum of healthcare solutions today to deliver the breakthroughs of tomorrow and profoundly impact health for humanity. Learn more at or at Follow us at @JNJInnovMed. Janssen Research & Development, LLC and Janssen Biotech, Inc. are Johnson & Johnson companies. CAUTIONS CONCERNING FORWARD-LOOKING STATEMENTS This press release contains "forward-looking statements" as defined in the Private Securities Litigation Reform Act of 1995 regarding product development and the potential benefits and treatment impact of nipocalimab. The reader is cautioned not to rely on these forward-looking statements. These statements are based on current expectations of future events. If underlying assumptions prove inaccurate or known or unknown risks or uncertainties materialize, actual results could vary materially from the expectations and projections of Janssen Research & Development, LLC, Janssen Biotech, Inc. and/or Johnson & Johnson. Risks and uncertainties include, but are not limited to: challenges and uncertainties inherent in product research and development, including the uncertainty of clinical success and of obtaining regulatory approvals; uncertainty of commercial success; manufacturing difficulties and delays; competition, including technological advances, new products and patents attained by competitors; challenges to patents; product efficacy or safety concerns resulting in product recalls or regulatory action; changes in behavior and spending patterns of purchasers of health care products and services; changes to applicable laws and regulations, including global health care reforms; and trends toward health care cost containment. A further list and descriptions of these risks, uncertainties and other factors can be found in Johnson & Johnson's most recent Annual Report on Form 10-K, including in the sections captioned "Cautionary Note Regarding Forward-Looking Statements" and "Item 1A. Risk Factors," and in Johnson & Johnson's subsequent Quarterly Reports on Form 10-Q and other filings with the Securities and Exchange Commission. Copies of these filings are available online at , or on request from Johnson & Johnson. None of Janssen Research & Development, LLC, Janssen Biotech, Inc. nor Johnson & Johnson undertakes to update any forward-looking statement as a result of new information or future events or developments. 1 Antozzi, C et al., Long-Term Safety and Efficacy of Nipocalimab in Generalized Myasthenia Gravis: Vivacity-MG3 Open-Label Extension Phase Results. Abstract #022 for poster presentation at 2025 American Academy of Neurology Congress. April 2025. 2 Nowak R et al., Efficacy of Nipocalimab, a Novel Neonatal Fragment Crystallizable Receptor Blocker, as Measured using Quantitative Myasthenia Gravis Assessment: Findings from the Phase 3 Placebo-Controlled Vivacity-MG3 Study. Abstract #001 for oral presentation at 2025 American Academy of Neurology Congress. April 2025. 3 Wolfe GI Myasthenia gravis activities of daily living profile. Neurology. 1999;22;52(7):1487-9. doi: 10.1212/wnl.52.7.1487. 4 Yin J, et al. A multicenter, randomized, open-label, phase 2 clinical study of telitacicept in adult patients with generalized myasthenia gravis. Eur J Neurol. 2024 Aug;31(8):e16322. doi: 10.1111/ene.16322. 5 Chen J, Tian D-C, Zhang C, et al. Incidence, mortality, and economic burden of myasthenia gravis in China: A nationwide population-based study. The Lancet Regional Health - Western Pacific. 2020;5(100063). . 6 Bacci ED et al. Understanding side effects of therapy for myasthenia gravis and their impact on daily life. BMC Neurol. 2019;19(1):335. 7 Wiendl, H., et al., Guideline for the management of myasthenic syndromes. Therapeutic advances in neurological disorders, 16, 17562864231213240. . Last accessed: April 2025. 8 Bubuioc A, et al. The epidemiology of myasthenia gravis. Journal of Medicine & Life (2021). Jan-Mar;14(1):7-16. doi: 10.25122/jml-2020-0145. 9 Ye, Yun et al. Epidemiology of myasthenia gravis in the United States. Frontiers in neurology vol. 15 1339167. 16 Feb. 2024, doi:10.3389/fneur.2024.1339167. 10 Dresser, Laura et al. Myasthenia Gravis: Epidemiology, Pathophysiology and Clinical Manifestations. Journal of clinical medicine vol. 10,11 2235. 21 May. 2021, doi:10.3390/jcm10112235. 11 J&J. Data on file. 12 Evoli A, Batocchi AP, Bartoccioni E, Lino MM, Minisci C, Tonali P. Juvenile myasthenia gravis with prepubertal onset. Neuromuscul Disord. 1998 Dec;8(8):561-7. doi: 10.1016/s0960-8966(98)00077-7. 13 Evoli A. Acquired myasthenia gravis in childhood. Curr Opin Neurol. 2010 Oct;23(5):536-40. doi: 10.1097/WCO.0b013e32833c32af. 14 Finnis MF, Jayawant S. Juvenile myasthenia gravis: a paediatric perspective. Autoimmune Dis. 2011;2011:404101. doi: 10.4061/2011/404101. 15 Haliloglu G, Anlar B, Aysun S, Topcu M, Topaloglu H, Turanli G, Yalnizoglu D. Gender prevalence in childhood multiple sclerosis and myasthenia gravis. J Child Neurol. 2002 May;17(5):390-2. doi: 10.1177/088307380201700516. 16 Parr JR, Andrew MJ, Finnis M, Beeson D, Vincent A, Jayawant S. How common is childhood myasthenia? The UK incidence and prevalence of autoimmune and congenital myasthenia. Arch Dis Child. 2014 Jun;99(6):539-42. doi: 10.1136/archdischild-2013-304788. 17 Mansukhani SA, Bothun ED, Diehl NN, Mohney BG. Incidence and Ocular Features of Pediatric Myasthenias. Am J Ophthalmol. 2019 Apr;200:242-249. doi: 10.1016/j.ajo.2019.01.004. 18 National Institute of Neurological Disorders and Stoke. Myasthenia Gravis. Available at: . Last accessed: April 2025. 19 Bever, C.T., Jr, Aquino, A.V., Penn, A.S., Lovelace, R.E. and Rowland, L.P. (1983), Prognosis of ocular myasthenia. Ann Neurol., 14: 516-519. . 20 Kupersmith MJ, Latkany R, Homel P. Development of generalized disease at 2 years in patients with ocular myasthenia gravis. Arch Neurol. 2003 Feb;60(2):243-8. doi: 10.1001/archneur.60.2.243. PMID: 12580710. 21 Myasthenia gravis fact sheet. Retrieved April 2024 from . 22 Myasthenia Gravis: Treatment & Symptoms. (2021, April 7). Retrieved April 2024 from . 23 DRG EPI (2021) & Optum Claims Analysis Jan 2012-December 2020. 24 O'Connell K, Ramdas S, Palace J. Management of Juvenile Myasthenia Gravis. Front Neurol. 2020 Jul 24;11:743. doi: 10.3389/fneur.2020.00743. PMID: 32793107; PMCID: PMC7393473. 25 Antozzi, C et al., Nipocalimab in Generalized Myasthenia Gravis: Results from a Double-Blind, Placebo-Controlled, Randomized Phase 3 Study. Abstract at 2024 European Academy of Neurology Congress. June 2024. 26 ClinicalTrials.gov Identifier: NCT04951622. Available at: . Last accessed: April 2025. 27 ClinicalTrials.gov. NCT03842189. Available at: . Last accessed: April 2025. 28 ClinicalTrials.gov Identifier: NCT05327114. Available at: . Last accessed: April 2025. 29 ClinicalTrials.gov Identifier: NCT04119050. Available at: . Last accessed: April 2025. 30 ClinicalTrials.gov Identifier: NCT05379634. Available at: . Last accessed: April 2025. 31 ClinicalTrials.gov Identifier: NCT05912517. Available at: . Last accessed: April 2025. 32 ClinicalTrials.gov Identifier: NCT06028438. Available at: . Last accessed: April 2025. 33 ClinicalTrials.gov Identifier: NCT04968912. Available at: . Last accessed: April 2025. 34 ClinicalTrials.gov Identifier: NCT04882878. Available at: . Last accessed: April 2025. 35 Lobato G, Soncini CS. Relationship between obstetric history and Rh(D) alloimmunization severity. Arch Gynecol Obstet. 2008 Mar;277(3):245-8. DOI: 10.1007/s00404-007-0446-x. 36 Roy S, Nanovskaya T, Patrikeeva S, et al. M281, an anti-FcRn antibody, inhibits IgG transfer in a human ex vivo placental perfusion model. Am J Obstet Gynecol. 2019;220(5):498 e491-498 e499. SOURCE Johnson & Johnson WANT YOUR COMPANY'S NEWS FEATURED ON PRNEWSWIRE.COM? 440k+ Newsrooms & Influencers 9k+ Digital Media Outlets 270k+ Journalists Opted In GET STARTED