FP Receptor

Latanoprostene bunod (LBN) is a topical ophthalmic therapeutic for the reduction of intraocular pressure (IOP) in patients with open-angle glaucoma or ocular hypertension (OHT). LBN is composed of latanoprost acid (LA) linked to a nitric oxide (NO)-donating moiety and is the first NO-releasing prostaglandin analog to be submitted for marketing authorization in the United States. The role of latanoprost in increasing uveoscleral outflow of aqueous humor (AqH) is well established[1].

Pharmacokinetic studies in rabbits and corneal homogenates indicate that LBN is rapidly metabolized to LA and butanediol mononitrate (BDMN). NO is subsequently released by BDMN as shown by increased cyclic guanosine monophosphate (cGMP) levels in (1) the AqH and iris-ciliary body after administration of LBN in rabbits and in (2) human trabecular meshwork (TM) cells after incubation with LBN. LBN reduced myosin light chain phosphorylation, induced cytoskeletal rearrangement, and decreased resistance to current flow to a greater extent than latanoprost in TM cells, indicating that NO released from LBN elicited TM cell relaxation. LBN also lowered IOP to a greater extent than latanoprost in FP receptor knockout mice, rabbits with transient OHT, glaucomatous dogs, and primates with OHT. Along with results from a Phase 2 clinical study in which treatment with LBN 0.024% resulted in greater IOP-lowering efficacy than latanoprost 0.005%, these data indicate that LBN has a dual mechanism of action, increasing AqH outflow through both the uveoscleral (using LA) and TM/Schlemm's canal (using NO) pathways[1].

Methods: The effect of Latanoprostene bunod (LBN) (1-100 μM) on HTMC cGMP levels was determined by ELISA with or without the soluble guanylate cyclase (sGC) inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ). Endothelin-1 (ET-1) was used to induce HTMC contractility. To determine the effect of LBN on myosin light chain-2 (MLC-2) phosphorylation, HTMCs were pretreated with 10 to 60 μM LBN for 1 hour and then ET-1 for 5 minutes. MLC-2 phosphorylation was determined by Western blotting. Effects of LBN (30 and 45 μM) on ET-1-induced filamentous (F)-actin cytoskeletal stress fibers and the focal adhesion associated protein vinculin were determined by confocal microscopy. ET-1-induced HTMC monolayer resistance in the presence of LBN (45 μM) was determined by electrical cell substrate impedance sensing, as an indicator of cell contractility. Latanoprost and SE 175 (an NO donor which releases NO on reductive transformation within the cells) were used as comparators in all studies.[2]

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Results: LBN (1-100 μM) significantly increased cGMP levels in a dose-dependent manner, with a half maximal effective concentration (EC50) of 1.5 ± 1.3 μM, and with maximal effect similar to that of 100 μM SE 175. In contrast, latanoprost caused a minimal increase in cGMP levels at 100 μM only. The cGMP elevation induced by LBN or SE 175 was abolished by ODQ and was therefore sGC-dependent. The two NO donors SE 175 and LBN elicited a reduction in ET-1-induced MLC-2 phosphorylation that was significantly greater than that mediated by latanoprost in HTMCs. SE 175 (100 μM) and LBN (30 or 45 μM) caused a dramatic reduction in ET-1-induced actin stress fibers and vinculin localization at focal adhesions, whereas 45 μM latanoprost was without observable effect. SE 175 reduced ET-1-induced increases in HTMC resistance in a dose-dependent manner. A synergistic effect on reduction of HTMC resistance was observed when latanoprost and SE 175 doses were given together. LBN significantly reduced ET-1-induced HTMC monolayer resistance increases to a greater extent than latanoprost, indicating a greater reduction in cell contractility with LBN.[2]

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Conclusions: LBN, SE 175, and latanoprost caused relaxation of ET-1-contracted HTMCs. The effect on HTMC relaxation observed with LBN was significantly greater in magnitude than that observed with latanoprost or SE 175. Data indicate that the NO-donating moiety of LBN mediates HTMC relaxation through activation of the cGMP signaling pathway and a subsequent reduction in MLC-2 phosphorylation. These findings suggest that increased conventional outflow facility may mediate the additional IOP-lowering effects of LBN over that of latanoprost observed in in vivo studies.[2]

The effect of BOL-303259-X (also known as NCX 116 and PF-3187207) on intraocular pressure (IOP) was investigated in monkeys with laser-induced ocular hypertension, dogs with naturally-occurring glaucoma and rabbits with saline-induced ocular hypertension. Latanoprost was used as reference drug. NO, downstream effector cGMP, and latanoprost acid were determined in ocular tissues following BOL-303259-X administration as an index of prostaglandin and NO-mediated activities. In primates, a maximum decrease in IOP of 31% and 35% relative to baseline was achieved with BOL-303259-X at doses of 0.036% (9 μg) and 0.12% (36 μg), respectively. In comparison, latanoprost elicited a greater response than vehicle only at 0.1% (30 μg) with a peak effect of 26%. In glaucomatous dogs, IOP decreased from baseline by 44% and 10% following BOL-303259-X (0.036%) and vehicle, respectively. Latanoprost (0.030%) lowered IOP by 27% and vehicle by 9%. Intravitreal injection of hypertonic saline in rabbits increased IOP transiently. Latanoprost did not modulate this response, whereas BOL-303259-X (0.036%) significantly blunted the hypertensive phase. Following BOL-303259-X treatment, latanoprost acid was significantly elevated in rabbit and primate cornea, iris/ciliary body and aqueous humor as was cGMP in aqueous humor. BOL-303259-X lowered IOP more effectively than latanoprost presumably as a consequence of a contribution by NO in addition to its prostaglandin activity. The compound is now in clinical development for the treatment of glaucoma and ocular hypertension[3].

Absorption, Distribution and Excretion
In a study with 22 healthy subjects monitored for 28 days, there were no quantifiable plasma concentrations of latanoprostene bunod (Lower Limit Of Quantitation, LLOQ, of 10.0 pg/mL) or butanediol mononitrate (LLOQ of 200 pg/mL) post daily dose of one drop bilaterally in the morning on Day 1 and 28. The mean time of maximum plasma concentration (Tmax) for latanoprost acid was about 5 minutes post dosage on both Day 1 and 28 of therapy. The mean maximum plasma concentrations (Cmax) of latanoprost acid (LLOQ of 30 pg/mL) were 59.1 pg/mL on Day 1 and 28, respectively.
The latanoprost acid component of latanoprostene bunod is predominantly metabolized by the liver and excreted primarily in the urine.
Unfortunately there have been no formal ocular distribution studies performed in humans at this time.
Since latanoprost acid plasma concentration dropped below the LLOQ (Lower Limit Of Quantitation) of 30 pg/mL in the majority of study subjects by 15 minutes following ordinary ocular administration, the elimination of latanoprost acid from human plasma is considered rapid.

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Metabolism / Metabolites
Upon topical administration at the ocular surface, latanoprostene bunod undergoes rapid carboxyl ester hydrolysis by endogenous corneal esterases into latanoprost acid and butanediol mononitrate. After the latanoprost acid reaches the systemic circulation, it is largely metabolized by the liver to the 1,2-dinor and 1,2,3,4-tetranor metabolites by way of fatty acid beta-oxidation. The butanediol monohidrate undergoes further metabolism (reduction) to 1,4-butanediol and nitric oxide (NO). Furthermore, this 1,4-butanediol metabolite is further oxidized to succinic acid that is subsequently then primarily taken up as a component in the tricarboxylic acid (TCA) cycle in cellular aerobic respiration.

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Biological Half-Life
The half-life after application of latanoprostene bunod in rabbits was 1.8 hours in cornea, 2.1 hours in aqueous humor, and 4.6 hours in the iris/ciliary body.

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
No information is available on the use of latanoprostene bunod during breastfeeding. Because of the extremely low levels in plasma after application to the eye and short half-life, it is not likely to reach the breastmilk or bloodstream of the infant or to cause any adverse effects in breastfed infants. Professional guidelines consider prostaglandin eye drops acceptable during breastfeeding. To further diminish the amount of drug that reaches the breastmilk after using eye drops, place pressure over the tear duct by the corner of the eye for 1 minute or more, then remove the excess solution with an absorbent tissue.
◉ Effects in Breastfed Infants
Relevant published information was not found as of the revision date.
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

[1]. The Role of Nitric Oxide in the Intraocular Pressure Lowering Efficacy of Latanoprostene Bunod: Review of Nonclinical Studies. J Ocul Pharmacol Ther. 2018 Jan/Feb;34(1-2):52-60.

Pharmacodynamics
Upon applying an appropriate dose of latanoprost bunod, reduction in intraocular pressure begins approximately 1 to 3 hours later with a maximum intraocular pressure reduction effect demonstrated after 11 to 13 hours.

507.283

C, 63.89; H, 8.14; N, 2.76; O, 25.21

860005-21-6

11156438

Colorless to light yellow ointment

4.289

3

8

18

36

646

5

C1[C@H]([C@@H]([C@H]([C@H]1O)C/C=C\CCCC(=O)OCCCCO[N+](=O)[O-])CC[C@H](CCC2=CC=CC=C2)O)O

LOVMMUBRQUFEAH-UIEAZXIASA-N

InChI=1S/C27H41NO8/c29-22(15-14-21-10-4-3-5-11-21)16-17-24-23(25(30)20-26(24)31)12-6-1-2-7-13-27(32)35-18-8-9-19-36-28(33)34/h1,3-6,10-11,22-26,29-31H,2,7-9,12-20H2/b6-1-/t22-,23+,24+,25-,26+/m0/s1

4-Nitrooxybutyl (Z)-7-[(1R,2R,3R,5S)-3,5-dihydroxy-2-[(3R)-3-hydroxy-5-phenylpentyl]cyclopentyl]hept-5-enoate

PF-3187207; NCX116; PF3187207; NCX-116; PF 3187207; Latanoprostene BUNOD; BOL-303259-X; NCX116; Vesneo; Vyzulta; Latanoprostene BUNOD; 860005-21-6; Vyzulta; PF-3187207; NCX 116; BOL-303259-X; NCX-116; Vesneo;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~100 mg/mL (~197.00 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (4.92 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in 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 25.0 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.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (4.10 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 20.8 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.

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Solubility in Formulation 3: ≥ 2.08 mg/mL (4.10 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 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)