Rilematovir (JNJ678; JNJ-53718678; JNJ-678; JNJ53718678) is a novel, oral and potent fusion protein inhibitor with antiviral activity. It is currently in clinical trials for treating respiratory syncytial virus (RSV). Oral treatment of neonatal lambs with JNJ-53718678, or with an equally active close analog, efficiently inhibits established acute lower respiratory tract infection in the animals, even when treatment is delayed until external signs of respiratory syncytial virus illness have become visible. Together, these data suggest that JNJ-53718678 is a promising candidate for further development as a potential therapeutic in patients at risk to develop respiratory syncytial virus acute lower respiratory tract infection.Respiratory syncytial virus causes lung infections in children, immunocompromised adults, and in the elderly.

Physicochemical Properties

Molecular Formula	C21H20CLF3N4O3S
Molecular Weight	500.92
Exact Mass	500.089
Elemental Analysis	C, 50.35; H, 4.02; Cl, 7.08; F, 11.38; N, 11.18; O, 9.58; S, 6.40
CAS #	1383450-81-4
PubChem CID	118892432
Appearance	White to off-white solid powder
Density	1.5±0.1 g/cm3
Boiling Point	672.5±55.0 °C at 760 mmHg
Flash Point	360.5±31.5 °C
Vapour Pressure	0.0±2.1 mmHg at 25°C
Index of Refraction	1.634
LogP	3.19
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	7
Rotatable Bond Count	7
Heavy Atom Count	33
Complexity	825
Defined Atom Stereocenter Count	0
SMILES	ClC1C=CC2=C(C=1)C=C(CN1C(N(CC(F)(F)F)C3C=CN=CC1=3)=O)N2CCCS(C)(=O)=O
InChi Key	GTQTUABHRCWVLL-UHFFFAOYSA-N
InChi Code	InChI=1S/C21H20ClF3N4O3S/c1-33(31,32)8-2-7-27-16(10-14-9-15(22)3-4-17(14)27)12-28-19-11-26-6-5-18(19)29(20(28)30)13-21(23,24)25/h3-6,9-11H,2,7-8,12-13H2,1H3
Chemical Name	3-((5-chloro-1-(3-(methylsulfonyl)propyl)-1H-indol-2-yl)methyl)-1-(2,2,2-trifluoroethyl)-1,3-dihydro-2H-imidazo[4,5-c]pyridin-2-one
Synonyms	JNJ-678; JNJ-53718678; JNJ 678; JNJ53718678; JNJ678; JNJ 53718678
HS Tariff Code	2934.99.03.00
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

Targets	Fusion protein[1]
ln Vitro	Currently undergoing clinical evaluation in infants hospitalized for respiratory syncytial virus (RSV) infection is rilematovir, a small-molecule RSV fusion inhibitor. The prefusion conformation of the RSV F protein is where rimetavir binds. Rilematovir exhibits minimal cytotoxicity and strong antiviral activity. Apart from its efficacy against the RSV A2 strain, Rilematovir exhibits strong activity against several RSV strains belonging to both the A and B subtypes. HeLa cells are used in an RSV infection assay, and the EC50 is 460 pM[1].
ln Vivo	Neonatal lambs treated orally with Rilematovir or a close analog that is equally active effectively suppresses established acute lower respiratory tract infections in the animals, even in cases where treatment is postponed until the animals exhibit outward symptoms of respiratory syncytial virus illness[1].
Cell Assay	Using a cellular infectious assay in 96-well plates where Vero/TMPRSS2 cells are infected with recombinant hMPV65, the antiviral activity of JNJ-678 (JNJ-53718678) against hMPV is assessed. After treating cells with varying concentrations of JNJ-678 (JNJ-53718678), recombinant hMPV (1×104 PFU per well) is added. Viral replication is measured using fluorescence three days after virus exposure, and the EC50 is computed[1].
Animal Protocol	Rats [1] At 24, 48, and 72 hours following viral infection, cotton rats are given either a single dose or once-daily doses of 40 mg/kg JNJ-678 (JNJ-53718678) by oral gavage. In every experiment, the reduction in viral replication is contrasted with challenged animals that were given only the vehicle[1].
References	[1]. Therapeutic efficacy of a respiratory syncytial virus fusion inhibitor. Nat Commun. 2017 Aug 1;8(1):167.
Additional Infomation	Rilematovir is under investigation in clinical trial NCT04056611 (Effects of JNJ-53718678 in Adult and Adolescent Participants Who Had a Hematopoietic Stem Cell Transplantation and Who Are Infected With Respiratory Syncytial Virus (RSV)). Rilematovir is an orally available inhibitor of human respiratory syncytial virus (RSV) fusion protein (F protein), with potential antiviral activity. Upon oral administration, rilematovir specifically targets and binds to F protein on the viral surface, which inhibits RSV F protein-mediated fusion with the host cell membrane and prevents viral entry. This blocks RSV replication, reduces viral load, and decreases the severity of the disease. RSV F protein, a viral surface glycoprotein, plays a key role in RSV fusion with and entry into target cells.

Solubility Data

Solubility (In Vitro)

DMSO : 16~65 mg/mL ( 31.94~129.76 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.17 mg/mL (4.33 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 21.7 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: 2.17 mg/mL (4.33 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 21.7 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Solubility in Formulation 3: ≥ 2.17 mg/mL (4.33 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 21.7 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.. Solubility in Formulation 4: 10% DMSO+40% PEG300+5% Tween-80+45% Saline: ≥ 2.17 mg/mL (4.33 mM)  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	1.9963 mL	9.9816 mL	19.9633 mL
	5 mM	0.3993 mL	1.9963 mL	3.9927 mL
	10 mM	0.1996 mL	0.9982 mL	1.9963 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.