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].

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For IOP studies in mice, a single 3 μL topical ocular instillation of LBN (0.006%) or latanoprost (0.005%) was administered to one eye of anesthetized wild-type or FPKO mice. IOP was measured in anesthetized animals using a microneedle inserted into the anterior chamber connected to a pressure transducer at baseline and multiple time points post-dose.
In the rabbit transient OHT model, both eyes of anesthetized New Zealand White rabbits were injected intravitreally with 0.1 mL hypertonic saline to induce OHT. Immediately after, a 50 μL topical ocular dose of LBN (0.036%), latanoprost (0.030%), or vehicle was administered. IOP was measured using a Tono-Pen at baseline and several time points post-instillation.
In glaucomatous beagle dogs, a 50 μL topical ocular dose of LBN (0.036%) or latanoprost (0.030%) was administered to one eye, with the contralateral eye receiving vehicle. IOP was measured with a Tono-Pen at baseline and multiple time points post-dose.
In cynomolgus monkeys with laser-induced OHT in one eye, a 30 μL topical ocular dose of LBN (0.012%, 0.03%, or 0.12%) or the corresponding equimolar dose of latanoprost (0.010%, 0.03%, or 0.10%) or vehicle was administered in a randomized, masked, crossover design. IOP was measured in conscious animals using a pneumatonometer.
For pharmacokinetic and cGMP studies in rabbits, a single 30 or 50 μL topical ocular dose of LBN (0.012% or 0.036%) or equimolar latanoprost was administered. Animals were euthanized at specified time points, and ocular tissues (cornea, aqueous humor, iris-ciliary body) were collected for analysis of drug metabolite levels (by LC-MS/MS) or cGMP concentrations (by enzyme immunoassay).

Absorption, Distribution and Excretion
In a 28-day monitoring study of 22 healthy subjects, no concentrations of latanoprost bromide (lower limit of quantitation, LLOQ 10.0 pg/mL) or butylene mononitrate (LLOQ 200 pg/mL) were detected in plasma after bilateral administration of one drop on the mornings of days 1 and 28. The time to peak plasma concentration (Tmax) of latanoprost acid was approximately 5 minutes after administration on days 1 and 28. The mean peak plasma concentration (Cmax) of latanoprost acid (lower limit of quantitation 30 pg/mL) was 59.1 pg/mL on days 1 and 28, respectively. The latanoprost acid component of latanoprost bromide is primarily metabolized in the liver and excreted mainly in the urine. Unfortunately, no formal human ocular distribution studies have been conducted to date.
Because in most subjects, plasma concentrations of latanoprost acid drop below the lower limit of quantification (LLOQ) of 30 pg/mL within 15 minutes of routine ocular administration, clearance of latanoprost acid from human plasma is considered rapid.
Metabolism/Metabolites
After topical application to the ocular surface, latanoprost bromide is rapidly hydrolyzed into carboxylic acid esters by endogenous corneal esterases. Latanoprost is metabolized into latanoprost acid and butylene glycol mononitrate. After entering systemic circulation, latanoprost acid is primarily metabolized in the liver via fatty acid β-oxidation to 1,2-dinoprostate and 1,2,3,4-tetranorthate metabolites. Butylene glycol mononitrate is further metabolized (reduced) to 1,4-butanediol and nitric oxide (NO). Furthermore, the 1,4-butanediol metabolite is further oxidized to succinate, which is subsequently absorbed by cells primarily as a component of the tricarboxylic acid cycle (TCA cycle) and participates in aerobic respiration.

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Biological Half-Life
After application of latanoprost bronchospasm to rabbit eyes, its half-life was 1.8 hours in the cornea, 2.1 hours in the aqueous humor, and 4.6 hours in the iris/ciliary body.

Effects During Pregnancy and Lactation
◉ Overview of Use During Lactation
There is currently no information regarding the use of latanoprost bromide during lactation. Due to the extremely low plasma concentration and short half-life after eye drops, it is unlikely to enter breast milk or the infant's bloodstream, and it is unlikely to cause any adverse effects on breastfed infants. Professional guidelines consider the use of prostaglandin eye drops during lactation to be acceptable. To further reduce the amount of medication that enters breast milk after eye drops, press the tear duct at the corner of the eye for at least 1 minute, then wipe away any excess medication with absorbent tissue.
◉ Effects on Breastfed Infants
No published information found as of the revision date.
◉ Effects on Breastfeeding and Breast Milk
No published information 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
Following administration of an appropriate dose of latanoprost bromide, intraocular pressure begins to decrease approximately 1 to 3 hours later, reaching its maximum decrease 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.)