JPH0797335A - Therapeutic agent for acute hepatic insufficiency - Google Patents

Abstract

PURPOSE:To obtain a therapeutic agent for acute hepatic insufficiency such as fulminant hepatitis or hepatic insufficiency after operation, containing activated protein C alone as active ingredient. CONSTITUTION:This therapeutic agent for acute hepatic insufficiency contains, as active ingredient, activated protein C alone. The activated protein C is pref. that derived from human blood or produced by the gene recombination technique. To maintain the activity of this activated protein C to the utmost, it is preferable that the activated protein C be used just after produced or within 5 days even after preserved at 4 deg.C; or, this agent can also be preserved after lyophilization together with a suitable stabilizer or by freezing its solution.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to activated protein C.
The present invention relates to a therapeutic agent for acute liver failure containing (APC) as an active ingredient. More specifically, the present invention is a therapeutic agent for fulminant hepatitis and the like containing activated protein C (APC) as an active ingredient.

[0002]

BACKGROUND OF THE INVENTION Fulminant hepatitis is a hepatic disease that rapidly develops within 8 weeks after the onset of hepatitis symptoms due to liver dysfunction due to a widespread necrosis of the hepatocyte group in hepatitis. A person with sexual coma as the main symptom and a prothrombin time (PT) of 40% or less of the normal value. It is a disease with a poor prognosis, often accompanied by serious complications such as gastrointestinal bleeding, renal failure, and infection during the course. There are also patients with severe and rapidly worsening liver failure that do not fit the above definition. There are also patients with severe and rapidly worsening liver failure who do not meet the above definition after surgery such as partial hepatectomy.

Although the pathogenic mechanism of acute hepatic failure such as fulminant hepatitis has not been fully elucidated, in the pathological analysis of patient's pathology, hypercoagulation of blood occurs in the hepatic sinus, which causes cell necrosis due to blood flow disorder. This is thought to lead to worsening of the disease state, since many suggestive findings have been observed.

For the treatment of acute liver failure such as fulminant hepatitis, systemic control such as plasma exchange and glucagon-insulin therapy with the expectation of liver regeneration are performed, but both are mainly coping therapy. , More effective treatments are needed.

On the other hand, activated protein C (APC) is
It is a serine protease having a molecular weight of 61,000 consisting of two chains and having an anticoagulant effect. This APC normally exists in blood as its precursor, protein C (PC), but it undergoes limited degradation by thrombin generated once the coagulation system operates, and expresses an enzyme activity.

APC is an activated factor VIII (FVIIIa) and factor V (FV) in the coagulation factor cascade.
Inhibiting a) suppresses thrombin production and exhibits anticoagulant action ( Biochemistry , 1977, 1
6 , 5824-5831, Biochem. Biophys. Acta ., 1
979, 571 , 333-342, Blood, 1982, 5
9 , 1067-1072, J. Biol. Chem. , 1982.
258 , 1914-1920, Biochemistry , 198.
0, 19 , 401-409). Also, APC is invitr
Since o also inhibits plasminogen activator inhibitor, it is considered that plasminogen activator may be indirectly added to exhibit fibrinolytic activity (Proc. Natl. Acad. Sci. USA, 1985, 82, 11
21-1125). Generalized intravascular coagulation (DI
APC that inactivates FVIIIa and FVa, although a strong anticoagulant action is required in the state of dynamically coagulating such as C)
Suppresses the production of thrombin, thereby blocking the production of FVIIIa and FVa by thrombin, that is, the positive feedback of the coagulation system, and is expected to have a strong anticoagulant effect. On the other hand, in the thrombus formation site such as DIC, the lack of thrombomodulin (TM) due to damage of vascular endothelial cells is considered. Especially when it is caused by endotoxin, TM activity may be decreased.
It seems that the conversion to PC is not enough. Therefore, high-purity APC is expected as an effective therapeutic drug by directly suppressing the hypercoagulable state such as DIC.

However, it has not been known that APC administration alone is effective for treating acute liver failure, and particularly effective for fulminant hepatitis among acute liver failure.

The inventors of the present invention have conducted extensive studies to develop a therapeutic agent for acute hepatic failure such as fulminant hepatitis, and as a result, a single preparation of activated protein C has been used as a therapeutic agent for acute liver failure such as fulminant hepatitis in humans and others. The present invention has been completed based on this finding.

[0009]

[Means for Solving the Problems] That is, the present invention is a therapeutic agent for acute liver failure, which substantially comprises activated protein C as an active ingredient.

In the present invention, activated protein C (hereinafter sometimes abbreviated as APC) means human,
It includes activated protein C obtained from blood of other mammals (activated protein C derived from blood) and activated protein C derived from humans and other mammals produced by gene recombination technology. The APC of the present invention includes, among these APCs, human blood-derived activated protein C or human activated protein C produced by a gene recombination technique. It should be noted that, as long as the effect of the present invention as a therapeutic agent for acute liver failure is obtained, it has physiologically equivalent activity to activated protein C derived from blood and activated protein C produced by gene recombination technology. Derivatives in which a part of the entire amino acid sequence of activated protein C is deleted, substituted, inserted or added are also included in activated protein C of the present invention.

The method for producing APC in the present invention is not particularly limited, but it may be produced by, for example, a method of activating PC separated from human blood, a method of separating APC from human blood, or a gene recombination technique. AP
C is included.

There is no particular limitation on the method of activating PC to APC, and it can be carried out by, for example, a method of activation by thrombin separated from blood of human or bovine or a method of activation by synthetic peptide.

The following methods are mentioned as a method for producing blood-derived APC. For example, anti-protein C from human plasma
Protein C purified by affinity chromatography using an antibody (preferably a monoclonal antibody) is activated by human thrombin and then purified by cation exchange chromatography (Blood, 63,
115-121, 1984), or by Kisiel,
PC obtained by purifying human plasma by steps such as adsorption / elution of citrate Ba, ammonium sulfate fractionation, DEAE-Sephadex column chromatography, dextran sulfate agarose chromatography and polyacrylamide gel electrophoresis was used to activate APC and APC. Method (J. Clin. Invest., 64, 761, 769, 197)
9), or a commercially available PC-containing blood coagulation preparation
yler et al. (J. Clin. Invest., 79, 918-92)
5, 1987) and activated to APC.

A method for preparing APC using the gene recombination technique is disclosed in, for example, JP-A-61-2205487.
No. 1, JP-A 1-2338 or JP-A 1-8508
No. 4, etc. are available.

In order to maintain the maximum activity of the APC prepared by the above method, the APC of the present invention is preferably fresh or, when stored at 4 ° C., within about 5 days after storage. . Alternatively, the APC of the present invention can be lyophilized and stored together with a suitable stabilizer, and further, the APC solution can be frozen and stored.

In the present invention, APC as an active ingredient is combined with a known appropriate excipient to prepare a parenteral administration preparation, preferably an intravenous administration preparation, by a known method, thereby treating the acute liver failure of the present invention. It can be an agent. The dose of APC varies depending on the symptoms, but is generally 20 per adult per day.
~ 1,000 U / kg body weight, preferably 50-30
It is advisable to administer 0 U / kg in 1 to 2 divided doses. The most suitable administration method is intravenous infusion. It should be noted that 1 U referred to here is the activated thromboplastin time (A
It means the amount that doubles PTT).

Blood-derived APC used in this example
Has been confirmed to be safe by a single intravenous administration test in mice, a general pharmacological test (effects on the respiratory circulatory system using Beagle dogs, etc.), and a virus inactivation test.

[0018]

The present invention will be described in more detail below with reference to examples.

[0019]

Example 1 This experiment was established as a model for fulminant hepatitis Gastroenterology, 99, 771-888, 199.
The method described in No. 0 was used as a reference.

Two-thirds of the Sprague-Dawley rat liver was excised under light anesthesia, and 48 hours later, endotoxin (Escherichia coli 026: B6-derived Difco) 20
0 μg / kg is administered intravenously. At the same time, 750 and 900 U / kg of APC (APC derived from blood: PC purified from plasma using the method of anion exchange treatment and immunoaffinity chromatography was obtained by activating thrombin) 750 and 900 U / kg were simultaneously administered from the femoral vein. . A physiological saline solution was administered to the control group.

After 5 hours, blood was collected from the jugular vein under anesthesia, and SGPT (serum glutamic pyruvic) was used as an index of liver damage.
transaminase) was measured. The results are shown in Table 1.
From Table 1, it was confirmed that APC suppresses liver damage in a fulminant hepatitis model [partial liver resection + endotoxin induction].

[0022]

[Table 1]

Claims (5)

[Claims] 1. A therapeutic agent for acute liver failure, which substantially comprises activated protein C as an active ingredient. 2. The acute liver failure is fulminant hepatitis.
The therapeutic agent described. 3. The therapeutic agent according to claim 1, wherein the acute hepatitis is postoperative liver failure. 4. The therapeutic agent according to claim 1, wherein the activated protein C is an activated protein C derived from human blood. 5. The therapeutic agent according to claim 1, wherein the activated protein C is human activated protein C produced by a gene recombination technique.