Drugs / Clesrovimab
Regulatory milestones approvals, filings & regulatory actions · 5 recorded
| Milestone | Jurisdiction | Brand | Indication | Date | Sentence it was read from |
|---|---|---|---|---|---|
| Filed lower respiratory tract disorder 1 milestone | |||||
| Filed | US (FDA) | ENFLONSIA | lower respiratory tract disorder | 2026-08-06 | “the U.S. Food and Drug Administration (FDA) has accepted a supplemental Biologics License Application (sBLA) for ENFLONSIA™ (clesrovimab-cfor)” merck.com ↗ |
| Filed respiratory syncytial virus infectious disease 3 milestones | |||||
| Filed | Japan (PMDA) | — | respiratory syncytial virus infectious disease | 2025-07-14 | “クレスロビマブ」について、生後初めてRSウイルス（respiratory syncytial virus）感染流行期を迎える新生児および乳児におけるRSウイルス感染症の予防薬として製造販売承認申請を行いました” msd.co.jp ↗ |
| Filed | US (FDA) | — | respiratory syncytial virus infectious disease | 2025-03-17 | “クレスロビマブに関する生物製剤承認申請（BLA）をFDAが受理しました。” msd.co.jp ↗ |
| Filed | US (FDA) | — | respiratory syncytial virus infectious disease | 2024-12-17 | “the U.S. Food and Drug Administration (FDA) has accepted the Biologics License Application (BLA) for clesrovimab (MK-1654)” merck.com ↗ |
| Approved Indication not stated 1 milestone | |||||
| Approved | EU (EMA) | Enflonsia | — | 2026-04-15 | europa.eu ↗ |
Trials 5
| Phase | Registry id | Dates | Indication | Sponsor | Status | Outcome |
|---|---|---|---|---|---|---|
| Phase 1/21 trial | ||||||
| Phase 1/2 | NCT03524118 | Sep 2018 → Sep 2022 | respiratory syncytial virus infectious disease | Merck Sharp & Dohme LLC | Completed | No outcome recorded |
| Phase 21 trial · 1 missed | ||||||
| Phase 2 | NCT04086472 | Oct 2019 → Mar 2020 | respiratory syncytial virus infectious disease | Merck Sharp & Dohme LLC | Completed | Missed primary |
| Phase 2/31 trial · 1 met primary | ||||||
| Phase 2/3 | NCT04767373 | Apr 2021 → Jul 2024 | respiratory syncytial virus infectious disease | Merck Sharp & Dohme LLC | Completed | Met primary |
| Phase 31 trial | ||||||
| Phase 3 | NCT04938830 | Nov 2021 → Apr 2025 | respiratory syncytial virus infectious disease | Merck Sharp & Dohme LLC | Completed | No outcome recorded |
| Phase 41 trial | ||||||
| Phase 4 | NCT07824167 | Sep 2026 → Mar 2028 expected | respiratory syncytial virus infectious disease | Emory University | Not yet recruiting | No outcome recorded |
News releases announcing trial results or a regulatory action · 19
| Date | Issuer | Release |
|---|---|---|
| 2026-08-07 | MSD R&D (China) Co., Ltd. | Regulatory 長期間作用型抗RSウイルスヒトモノクローナル抗体製剤「エヌフロンシア®」生後2回目のRSウイルス感染流行期を迎える重症化リスクが高い幼児に対するRSウイルス感染症予防の適応拡大を申請 msd.co.jp ↗ |
| 2026-08-06 | Merck Sharp & Dohme LLC | Regulatory U.S. FDA Accepts sBLA for ENFLONSIA™ (clesrovimab-cfor) to Update its Respiratory Syncytial Virus (RSV) Lower Respiratory Tract Disease Indication to Include Children Under Two Years at Increased Risk for Severe RSV for Their Second Season merck.com ↗ |
| 2026-06-19 | MSD R&D (China) Co., Ltd. | Regulatory すべての新生児および乳児を対象とする長期間作用型抗RSウイルスヒトモノクローナル抗体製剤「エヌフロンシア®」製造販売承認を取得～体重にかかわらず固定用量を1回筋肉内注射することで予防効果を発揮～ msd.co.jp ↗
MSD株式会社（本社：東京都千代田区、代表取締役社長：プラシャント・ニカム、以下「MSD」）は、本日、長期間作用型抗RSウイルスヒトモノクローナル抗体製剤「エヌフロンシア® 筋注シリンジ105mg」（一般名：クレスロビマブ（遺伝子組換え）、以下、エヌフロンシア®）について、以下の「効能又は効果」で製造販売承認を取得しましたのでお知らせいたします。 |
| 2026-04-17 | Merck Sharp & Dohme LLC | Regulatory European Commission Approves Merck’s ENFLONSIA™ (clesrovimab) for the Prevention of Respiratory Syncytial Virus (RSV) Lower Respiratory Tract Disease in Infants During Their First RSV Season merck.com ↗
The EC approval authorizes the marketing of ENFLONSIA in all 27 European Union (EU) member states, as well as Iceland, Liechtenstein and Norway. |
| 2026-03-11 | MSD R&D (China) Co., Ltd. | Results Merck & Co., Inc., Rahway, NJ, USA、ENFLONSIA™（clesrovimab）についてRSウイルス感染症の重症化リスクが高い2歳未満の乳幼児における生後2回にわたるRSウイルス感染流行期の良好な新データを公表 msd.co.jp ↗
Merck & Co., Inc., Rahway, NJ, USA（米国とカナダ以外ではMSD）は本日、RSウイルス（respiratory syncytial virus）感染症の重症化リスクが高い乳幼児を対象にENFLONSIA™（clesrovimab）の安全性、有効性、薬物動態を生後2回にわたるRSウイルス感染流行期を通して評価した第3相SMART試験（MK-1654-007、 NCT04938830 ）における、生後2回目のRSウイルス感染流行期の良好な結果を発表しました。 |
| 2026-02-19 | Merck Sharp & Dohme LLC | Results Merck Announces Positive New Data for ENFLONSIA™ (clesrovimab) for Infants and Children Under 2 Years of Age at Increased Risk for Severe Respiratory Syncytial Virus (RSV) Disease Over Two RSV Seasons merck.com ↗
Results from the SMART study support extrapolation of efficacy to children under 2 years of age at increased risk for severe RSV disease through RSV season 2. |
| 2025-09-19 | Merck Sharp & Dohme LLC | Regulatory Merck Receives Positive EU CHMP Opinion for ENFLONSIA™ (clesrovimab) for the Prevention of Respiratory Syncytial Virus (RSV) in Infants During Their First RSV Season merck.com ↗ |
| 2025-07-29 | Merck Sharp & Dohme LLC | Regulatory Merck & Co., Inc., Rahway, N.J., USA Announces Second-Quarter 2025 Financial Results msd.com ↗
Received FDA Approval of ENFLONSIA for Prevention of RSV Lower Respiratory Tract Disease in Infants Born During or Entering Their First RSV Season; CDC’s ACIP Recommended ENFLONSIA for Prevention of RSV in Infants Younger Than 8 Months of Age for Their First RSV Season |
| 2025-07-14 | MSD R&D (China) Co., Ltd. | Regulatory MSD株式会社 長期間作用型抗RSウイルスヒトモノクローナル抗体製剤「クレスロビマブ」について 生後初めてRSウイルス感染流行期を迎える新生児および乳児における RSウイルス感染症の予防薬として承認を申請 msd.co.jp ↗
MSD株式会社（本社：東京都千代田区、代表取締役社長：プラシャント・ニカム、以下 「MSD」）は、本日、長期間作用型抗RSウイルスヒトモノクローナル抗体製剤「クレスロビマブ」について、生後初めてRSウイルス（respiratory syncytial virus）感染流行期を迎える新生児および乳児におけるRSウイルス感染症の予防薬として製造販売承認申請を行いましたのでお知らせいたします。 |
| 2025-06-26 | Merck Sharp & Dohme LLC | Regulatory ACIP Recommends Use of Merck’s ENFLONSIA™ (clesrovimab-cfor) for Prevention of Respiratory Syncytial Virus (RSV) Lower Respiratory Tract Disease in Infants Younger than 8 Months of Age Born During or Entering Their First RSV Season merck.com ↗
The ACIP also voted to include ENFLONSIA in the Vaccines for Children Program—an important step in ensuring broad access to this preventive option for infants. |
| 2025-06-09 | Merck Sharp & Dohme LLC | Regulatory U.S. FDA Approves Merck’s ENFLONSIA™ (clesrovimab-cfor) for Prevention of Respiratory Syncytial Virus (RSV) Lower Respiratory Tract Disease in Infants Born During or Entering Their First RSV Season merck.com ↗
Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced the U.S. Food and Drug Administration (FDA) has approved ENFLONSIA™ (clesrovimab-cfor) for the prevention of respiratory syncytial virus (RSV) lower respiratory tract disease in neonates (newborns) and infants who are born during or entering their first RSV season. |
| 2024-12-17 | Merck Sharp & Dohme LLC | Regulatory Merck Announces FDA Acceptance of Biologics License Application for Clesrovimab, an Investigational Long-Acting Monoclonal Antibody Designed to Protect Infants from RSV Disease During their First RSV Season merck.com ↗
The FDA has set a Prescription Drug User Fee Act (PDUFA), or target action, date of June 10, 2025. |
| 2024-11-07 | MSD R&D (China) Co., Ltd. | Results 抗RSウイルスモノクローナル抗体として開発中のクレスロビマブ（MK-1654）により 健康な早産児および正期産児のRSウイルス感染症の発生率と入院率が有意に低下 msd.co.jp ↗
健康な早産児および正期産児（出生から1歳を迎えるまで）を対象にクレスロビマブの単回投与を評価するプラセボ対照第2b/3相試験のMK-1654-004では、事前に規定されたすべての評価項目を達成し、5カ月および6カ月の時点で一貫した結果が得られました。 |
| 2024-10-17 | Merck Sharp & Dohme LLC | Results MSD’s Clesrovimab (MK-1654), an Investigational Respiratory Syncytial Virus (RSV) Preventative Monoclonal Antibody, Significantly Reduced Incidence of RSV Disease and Hospitalization in Healthy Preterm and Full-term Infants msd.com ↗
In the Phase 2b/3 trial, clesrovimab reduced RSV-associated hospitalizations (secondary endpoint) and RSV-associated lower respiratory infection hospitalizations (tertiary endpoint) by more than 84% and 90%, respectively, through 5 months |
| 2024-10-17 | Merck Sharp & Dohme LLC | Results Merck’s Clesrovimab (MK-1654), an Investigational Respiratory Syncytial Virus (RSV) Preventative Monoclonal Antibody, Significantly Reduced Incidence of RSV Disease and Hospitalization in Healthy Preterm and Full-term Infants merck.com ↗
In the Phase 2b/3 trial, clesrovimab reduced RSV-associated hospitalizations (secondary endpoint) and RSV-associated lower respiratory infection hospitalizations (tertiary endpoint) by more than 84% and 90%, respectively, through 5 months |
| 2024-08-30 | MSD R&D (China) Co., Ltd. | Results Merck & Co., Inc., Rahway, NJ, USA2024年度第2四半期決算発表 msd.co.jp ↗
当社は、乳児における呼吸器合胞体ウイルス（RSV）予防用モノクローナル抗体であるClesrovimab（MK-1654）の第2b/3相試験の良好な結果を発表しました（すべての主要安全性評価項目および有効性評価項目を達成）。 |
| 2024-07-30 | Merck Sharp & Dohme LLC | Results Merck Announces Second-Quarter 2024 Financial Results merck.com ↗
Announced Positive Results From Phase 2b/3 Trial of Clesrovimab (MK-1654), an Investigational RSV Preventative Monoclonal Antibody for Infants |
| 2024-07-23 | Merck Sharp & Dohme LLC | Results MSD Announces Topline Results from Phase 2b/3 Trial of Clesrovimab (MK-1654), an Investigational Respiratory Syncytial Virus Preventative Monoclonal Antibody for Infants msd.com ↗
In the trial, clesrovimab met its primary safety and efficacy endpoints, including reducing medically attended lower respiratory infections (MALRI) caused by RSV through Day 150. |
| 2024-07-23 | Merck Sharp & Dohme LLC | Results Merck Announces Topline Results from Phase 2b/3 Trial of Clesrovimab (MK-1654), an Investigational Respiratory Syncytial Virus Preventative Monoclonal Antibody for Infants merck.com ↗ |
All press releases naming this drug 19 releases
Evidence & citations 5 cited values
Every value below carries the sentence it was read from. 6 sources stand behind the page.
| Field | Value | Cited text |
|---|---|---|
| Known as | Clesrovimab | ClinicalTrials.gov intervention name — accepted as the source's own label NCT04938830 ↗ |
| Known as | MK-1654 | “MK-1654” NCT04086472 ↗ |
| Action | Inhibit | “Respiratory Syncytial Virus Neutralizing Antibody, Clesrovimab” PMID 39601265 ↗ Mar 2025 |
| Modality | Monoclonal antibody | “Clesrovimab is an investigational monoclonal antibody” PMID 39601265 ↗ Mar 2025 |
| Route | Intramuscular | “Single ascending doses of clesrovimab will be administered via IM injection.” NCT03524118 ↗ |