Multiple myeloma cell growth is inhibited by nelfinavir (AG1341) (1-10 μM; 48) [4]. Fresh nelfinavir (1-10 μM; 17 hours) causes inflammation in multiple myeloma cell lines and inhibits 26S chymotrypsin amyloid chromosomal activity, damages ischemia, and causes cellular burst in myeloma cell lines [4]. [4] Nelfinavir (5 μM; 0–24 hours) decreases AKT phosphorylation. Anise dye increases caspase-3 stability, decreases ERK1/2, AKT, and STAT-3 phosphorylation, and activates the unfolded protein response system [4]. Another SARS-CoV 3CL pro adaptor with an IC50 of 35.93 μM is nelfinavir.

In NOD/SCID mice, nelfinavir (AG1341) (75 mg/kg; i.p.; 5 days per week for 21 days) inhibits the proliferation of multiple myeloma cells [4].

Cell proliferation assay [4]
Cell Types: RPMI, LP1, U266, OPM2 and MM1S Cell
Tested Concentrations: 1, 2, 5, 10 μM
Incubation Duration: 48 hrs (hours)
Experimental Results: Inhibition of RPMI , LP1, U266, proliferation. OPM2 and MM1S cell lines were dose-dependent, with IC50 of 1-5 μM.

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Apoptosis analysis [4]
Cell Types: LP1 and U266 Cell
Tested Concentrations: 1-10 μM
Incubation Duration: 17 hrs (hours)
Experimental Results: A dose-dependent increase in the percentage of Annexin V+/propidium iodide+ cells was induced.

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Western Blot Analysis [4]
Cell Types: U266 cells
Tested Concentrations: 5 μM
Incubation Duration: 0-24 hrs (hours)
Experimental Results: AKT phosphorylation level diminished in U266 cells.

Animal/Disease Models: NOD/SCID (severe combined immunodeficient) mouse (carrying U266-luc cells) [4]
Doses: 75 mg/kg
Route of Administration: intraperitoneal (ip) injection; 5 days a week for 21 days
Experimental Results: MM cells in NOD/SCID (severe combined immunodeficient) mouse diminished growth.

Absorption, Distribution and Excretion
Good absorption after oral administration. Most (87%) of the oral 750 mg dose of 14C-nelfinavir is recovered in feces; fecal radioactivity consists of various oxidative metabolites (78%) and unmetabolized nelfinavir (22%). Only 1–2% of the dose is recovered in urine, primarily unmetabolized nelfinavir. The apparent volume of distribution after oral administration of nelfinavir is 2–7 L/kg. Estimated oral clearance after a single dose (24–33 L/h) and multiple doses (26–61 L/h) indicate that nelfinavir is a drug with moderate to high hepatic bioavailability. Metabolites/Metabolites After a single oral dose of 750 mg 14C-nelfinavir, unmetabolized nelfinavir accounts for 82–86% of the total plasma radioactivity. In vitro studies have shown that multiple cytochrome P-450 enzymes (including CYP3A and CYP2C19) are involved in the metabolism of nelfinavir. One major oxidative metabolite and several minor oxidative metabolites have been identified in plasma. The major oxidative metabolite exhibits in vitro antiviral activity comparable to the parent drug. Known metabolites of nelfinavir include 3,4-dihydroxynelfinavir and nelfinavir-hydroxytert-butylamide. The terminal half-life in plasma is typically 3.5 to 5 hours.

Hepatotoxicity
A significant proportion of patients taking antiretroviral regimens containing nelfinavir experience some degree of elevated serum transaminase levels. Moderate to severe elevations (more than 5 times the upper limit of normal) are seen in only 3% to 10% of patients, but the incidence may be higher in patients co-infected with HIV-HCV. These elevations are usually asymptomatic and self-limiting, returning to normal with continued use. Clinically significant acute liver injury caused by nelfinavir is rare. The few reported cases all occurred 1 to 8 weeks after starting nelfinavir; the pattern of serum enzyme elevation has not been reported, but it is likely hepatocellular (Case 1). Hypersensitivity reactions (fever, rash, eosinophilia) and autoantibody formation may occur, but these symptoms are not very pronounced. Acute liver injury caused by nelfinavir is usually self-limiting, but can also be severe; the sponsor has received reports of isolated cases of acute liver failure, but details are unavailable. In patients with co-infection with hepatitis B virus (HBV) or hepatitis C virus (HCV), some cases appear to be due to exacerbation of underlying chronic liver disease, possibly due to a sudden immune remodeling. There is no clear association between nelfinavir treatment and lactic acidosis and acute fatty liver, conditions commonly associated with several nucleoside analog reverse transcriptase inhibitors used to treat HIV infection. Probability Score: D (Possibly a rare cause of clinically significant liver injury).

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Effects During Pregnancy and Lactation
◉ Overview of Use During Lactation Nelfinavir is present in low concentrations in breast milk and is generally undetectable in the serum of breastfed infants. However, there is some evidence that adverse reactions to nelfinavir may occur in breastfed infants. Nelfinavir is not recommended for use during lactation. Achieving and maintaining viral suppression through antiretroviral therapy can reduce the risk of breast milk transmission to below 1%, but not zero. For HIV-infected individuals receiving antiretroviral therapy with a persistently low viral load, breastfeeding should be supported if they choose to do so. If viral load is not suppressed, pasteurized donor breast milk or formula is recommended.
◉ Impact of Breastfeeding on Infants
A study compared the incidence of rash, hepatotoxicity, and hyperbilirubinemia in 464 breastfed infants. The mothers of these infants were taking nelfinavir (n = 206) or nevirapine (n = 258) during pregnancy and postpartum, while also taking zidovudine and lamivudine to treat HIV infection. The researchers examined the infants at 1, 2, and 6 weeks postpartum. Seven infants (2.7%) exposed to nevirapine developed a moderate rash, and one infant (0.5%) exposed to nelfinavir developed a moderate rash. The median time of rash onset was 2 weeks postpartum. Four infants (1.9%) exposed to nelfinavir developed hepatotoxicity (3 moderate, 1 severe), while no hepatotoxicity occurred in infants exposed to nevirapine. Twenty-one infants (4.5%) developed high-risk hyperbilirubinemia, all within 48 hours of birth, but there was no difference in exposure levels between the two drugs.
◉ Effects on Lactation and Breast Milk
Gynecomastia has been reported in men receiving highly active antiretroviral therapy. Gynecomastia is initially unilateral, but about half of the cases develop into bilateral gynecomastia. No changes in serum prolactin levels were observed, and it usually resolves spontaneously within one year even with continued treatment. Some case reports and in vitro studies suggest that protease inhibitors may cause hyperprolactinemia and galactorrhea in some male patients, but this conclusion remains controversial. The implications of these findings for lactating women are unclear. Prolactin levels in established lactating mothers may not affect their ability to breastfeed.

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Protein binding
Nelfinavir binds extensively to proteins in serum (>98%).

[1]. Nelfinavir suppresses signaling and nitric oxide production by human aortic endothelial cells: protective effects of thiazolidinediones. Ochsner J. 2013 Spring;13(1):76-90.

[2]. Nelfinavir, A lead HIV protease inhibitor, is a broad-spectrum, anticancer agent that inducesendoplasmic reticulum stress, autophagy, and apoptosis in vitro and in vivo. Clin Cancer Res. 2007 Sep 1;13(17):5183-94.

[3]. Nelfinavir mesylate (AG1343): a potent, orally bioavailable inhibitor of HIV-1 protease. J Med Chem. 1997 Nov 21;40(24):3979-85.

[4]. The human immunodeficiency virus-1 protease inhibitor nelfinavir impairs proteasome activity and inhibits the proliferation of multiple myeloma cells in vitro and in vivo. Haematologica. 2012;97(7):1101‐1109.

[5]. Bardoxolone and bardoxolone methyl, two Nrf2 activators in clinical trials, inhibit SARS-CoV-2 replication and its 3C-like protease. Signal Transduct Target Ther. 2021 May 29;6(1):212.

Nelfinavir is an aryl thioether, used in the form of mesylate, to treat HIV infection and possesses certain anticancer properties. It is an HIV protease inhibitor and an antitumor drug. Nelfinavir belongs to the benzamide, phenol, aryl thioether, secondary alcohol, tertiary amine, and organic heterobicyclic compounds. It is the conjugate base of nelfinavir(1+). Nelfinavir is a potent HIV-1 protease inhibitor. It is used in combination with other antiviral drugs to treat HIV infection in adults and children. Nelfinavir inhibits the HIV viral protease, thereby preventing the cleavage of the gag-pol polyprotein, ultimately producing non-infectious immature viral particles. Nelfinavir is a protease inhibitor. Its mechanism of action is as an HIV protease inhibitor and a cytochrome P450 3A inhibitor. Nelfinavir is an antiretroviral protease inhibitor used to treat and prevent human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS). Nefernavir can cause a transient and usually asymptomatic increase in serum transaminase levels, but rarely causes clinically apparent acute liver injury. Liver injury occurring during antiretroviral therapy with nelfinavir in patients co-infected with hepatitis B virus (HBV) or hepatitis C virus (HCV) is likely due to an underlying exacerbation of chronic hepatitis B or C, rather than a direct effect of the drug. Nefernavir is a synthetic antiviral drug that selectively binds to and inhibits the human immunodeficiency virus (HIV) protease. Nefernavir is active against both HIV-1 and HIV-2. It is a potent HIV protease inhibitor. It is used in combination with other antiviral drugs to treat HIV infection in adults and children. See also: Nefernavir Mesylate (salt form). Drug Indications Used in combination with other antiviral drugs to treat HIV infection in adults and children.
FDA Label
Viracept is indicated for the treatment of HIV-1 infection in adults, adolescents, and children aged 3 years and older in combination with antiretroviral therapy. For patients previously treated with protease inhibitors (PIs), nelfinavir should be selected based on individual viral resistance testing and treatment history.

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Mechanism of Action
HIV viral proteases are important enzymes for HIV maturation and pathogenicity, as HIV produces its structural and key proteins in the form of polyproteins that require protease cleavage. The HIV protease is part of the Gag-pol polyprotein, where Gag encodes capsid and matrix proteins that form the outer protein shell of the virus; Pol encodes reverse transcriptase and integrase, responsible for synthesizing the viral genome and integrating it into the host cell. The Gag-pol polyprotein is hydrolyzed by the HIV protease to produce 66 molecules, which undergo conformational changes and become fully activated. Therefore, inhibiting the protease can prevent the HIV viral particle from fully maturing and losing its infectivity. Nelfinavir is a competitive inhibitor of the HIV protease. It prevents the enzyme from interacting with its substrate by reversibly binding to the enzyme's active site, thereby inhibiting the production of mature and infectious viral particles.

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Pharmacodynamics
Nelfinavir is a protease inhibitor effective against human immunodeficiency virus type 1 (HIV-1). Protease inhibitors block the protease moiety of HIV. The HIV-1 protease is an essential enzyme responsible for hydrolyzing the viral polyprotein precursor into the functional proteins that make up infectious HIV-1. Nelfinavir binds to the active site of the protease, inhibiting its activity. This inhibition prevents the cleavage of the viral polyprotein, thus avoiding the formation of immature, non-infectious viral particles. Protease inhibitors are almost always used in combination with at least two other anti-HIV drugs.

C32H45N3O4S

567.789

567.3131

C, 67.69; H, 7.99; N, 7.40; O, 11.27; S, 5.65

159989-64-7

Nelfinavir Mesylate;159989-65-8;Nelfinavir-d3;1217629-70-3

64143

White to off-white solid powder

1.22g/cm3

786.8ºC at 760 mmHg

429.7ºC

4.38E-26mmHg at 25°C

1.618

6.052

4

6

10

40

830

5

S(C1C([H])=C([H])C([H])=C([H])C=1[H])C([H])([H])[C@@]([H])([C@@]([H])(C([H])([H])N1[C@]([H])(C(N([H])C(C([H])([H])[H])(C([H])([H])[H])C([H])([H])[H])=O)C([H])([H])[C@]2([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[C@]2([H])C1([H])[H])O[H])N([H])C(C1C([H])=C([H])C([H])=C(C=1C([H])([H])[H])O[H])=O

QAGYKUNXZHXKMR-HKWSIXNMSA-N

InChI=1S/C32H45N3O4S/c1-21-25(15-10-16-28(21)36)30(38)33-26(20-40-24-13-6-5-7-14-24)29(37)19-35-18-23-12-9-8-11-22(23)17-27(35)31(39)34-32(2,3)4/h5-7,10,13-16,22-23,26-27,29,36-37H,8-9,11-12,17-20H2,1-4H3,(H,33,38)(H,34,39)/t22-,23+,26-,27-,29+/m0/s1

(3S,4aS,8aS)-N-tert-butyl-2-[(2R,3R)-2-hydroxy-3-[(3-hydroxy-2-methylbenzoyl)amino]-4-phenylsulfanylbutyl]-3,4,4a,5,6,7,8,8a-octahydro-1H-isoquinoline-3-carboxamide

Nelfinavir free base; AG-1343; AG 1343; AG1343; Nelfinavir; Viracept.

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 (176.12 mM

Solubility in Formulation 1: ≥ 2.5 mg/mL (4.40 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 25.0 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 2: ≥ 2.5 mg/mL (4.40 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 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 3: 10% DMSO+40% PEG300+5% Tween-80+45% Saline: ≥ 2.5 mg/mL (4.40 mM)

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