JPH0859508A - Cytomegalovirus retinitis preventive or therapeutic agent - Google Patents

Abstract

(57) [Abstract] [Objective] To provide a highly safe preventive or therapeutic agent for CMV retinitis with few side effects [Structure] Recognizing the envelope glycoprotein of CMV
An anti-CMV human monoclonal antibody that neutralizes V, such as regavirumab, is used as an active ingredient.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a preventive or therapeutic agent for CMV retinitis.

[0002]

2. Description of the Related Art Cytomegalovirus (hereinafter abbreviated as CMV) is a virus permanently infecting humans, and it is known that it is latent in various organs and often reactivates to cause opportunistic infections. Has been. Although CMV has a weak pathogenicity and is usually an inapparent infection, it is an opportunistic infection in immunocompromised patients such as those after various organ transplant surgery, cancer patients undergoing immunosuppressive therapy, and AIDS patients. Is listed as the first factor of. Pneumonia, hepatitis, gastroenteritis, retinitis, nephritis and the like are known as CMV infectious diseases. Among them, CMV retinitis is intractable and may cause serious blindness in the end. It is an eye disease.

[0003]

Ganciclovir has been commercially available as a therapeutic agent for CMV infection. Ganciclovir is a nucleic acid analog that is activated in CMV-infected cells, inhibits viral DNA polymerase, inhibits viral replication, and is reported to have a high efficacy rate of 71% against CMV retinitis ( Toru Masaoka et al., Treatment results of antiviral agent ganciclovir against cytomegalovirus infection, clinical and viral, 20, 59-70, 1992.
).

However, according to the above-mentioned report, serious side effects such as leukopenia, thrombocytopenia, pancytopenia, and hepatic dysfunction were observed in 35% of the administration cases, and ganciclovir was discontinued due to side effects. It is described that the number of cases was 11%. Considering that CMV infection often occurs in patients with deteriorated general condition, and the patients may be infants, it is desirable that the therapeutic agent has particularly few side effects.

In addition, it has been reported that a resistant virus appears in ganciclovir (A. Erice et al., PROGRESSIVE.
DISEASE DUE TO GANCICLOVIR-RESISTANT CYTOMEGALOVI
RUSIN IMMUNOCOMPROMISED PATIENTS, THE NEW ENGLAND
JOURNAL OF MEDICINE 320,289-300, 1989), the possibility of long-term continuous administration is at stake.

[0006] Therefore, it is an object of the present invention to provide a therapeutic agent for CMV retinitis which has no serious side effect and can be continuously administered for a long period of time.

[0007]

[Means for Solving the Problems] That is, the present invention prevents CMV retinitis using an anti-CMV human monoclonal antibody that recognizes an envelope glycoprotein of cytomegalovirus (CMV) and neutralizes CMV as an active ingredient. It is intended to provide a therapeutic agent.

Anti-CMV which is the active ingredient of the therapeutic agent of the present invention
As the human-type monoclonal antibody, a hybridoma method using human antibody-producing cells immunized with CMV envelope glycoprotein and mouse myeloma cells, or a human monoclonal antibody obtained by a transformation method using EB virus can be used. . Examples of human monoclonal antibodies by the hybridoma method include, for example, i
Mouse obtained by fusing human antibody-producing cells sensitized with CMV or a glycoprotein derived therefrom in the presence of mitogen in vitro and mouse myeloma cells
Mention may be made of anti-CMV human monoclonal antibodies produced by human hybridomas and / or cell lines derived therefrom.

As such an anti-CMV human monoclonal antibody, those recognizing CMV envelope glycoprotein B (Glycoprotein B) composed of a complex of subunits having a molecular weight of 130,000 daltons and 550,000 daltons are preferable.

As such an anti-CMV human type monoclonal antibody, there is a hybridoma C23 described in International Publication WO87 / 03602 or a human monoclonal antibody produced by a hybridoma that recognizes a glycoprotein similar to this hybridoma. Mention may be made of regaburumab. This monoclonal antibody
Reacts with CMV infected cells and barely with uninfected cells. In addition, it does not react with other herpes simplex viruses such as herpes simplex virus, EB virus, and varicella zoster virus, and is specific to CMV.

Regavirumab is an IgG1 antibody, C
It has the ability to neutralize MVs, and the amount of antibody required to control plaque formation of CMV by 50% is 0.5μ.
g / ml. In addition, intercellular C in vitro
Since it suppresses the spread of MV infection, it is presumed that it is possible to suppress the onset of CMV infection when administered to patients in the stage of CMV antigenemia.
When V is diagnosed, administration of regavirumab is effective in suppressing the spread of inflammation, reducing inflammation, and healing.

The CMV retinitis preventive or therapeutic agent of the present invention is preferably administered as an injection, and is preferably used for intravenous administration by infusion. The dose is preferably 0.4 to 50 mg / kg / week,
Administer 2.4 to 8 mg / kg / week. However, it is preferable that the initial administration be slightly larger.

The injectable composition can be manufactured by a conventional composition and method, and it is preferable to add a compound for stabilizing regavirumab such as human serum albumin or aminoacetic acid to the composition.

[0014]

The CMV of the present invention thus obtained
The preventive or therapeutic agent for retinitis is a highly safe therapeutic agent with few side effects such as transient mild fever and is highly safe. Therefore, it is administered to patients with immunodeficiency.
The spread of V retinitis can be suppressed, reduced, or cured. In addition, when regavirumab is used as the anti-CMV human monoclonal antibody, no antibody against regavirumab appears even during long-term administration, and continuous administration is possible.

[0015]

EXAMPLES The present invention will be described in more detail with reference to examples. The therapeutic agent, dose, administration method, diagnosis of CMV retinitis, detection of CMV antigen-positive cells, evaluation method and the like used in Examples were carried out as follows.

Therapeutic agent: TI-23 Using a freeze-dried product of regavirmab (containing 40 mg of regavirmab in 1 vial) obtained in Example 1 described later, it was dissolved in 20 ml of the distilled water for injection for dissolution to give 15 Intravenous infusion was administered over a period of minutes.

Dose and administration interval An initial dose of 200 mg / day once every 24 hours,
After continuous administration for 3 days, 120 mg / day was administered for 4 weeks as a maintenance administration at 1-week intervals from 1 week after the start of administration. When the investigator determined that maintenance administration was required after the 5th week, it was decided to additionally administer 120 mg once a week for 4 weeks. If the effect is insufficient and the blood concentration of regavirumab is significantly lower than 100 μg / ml, the dose will be increased up to 400 mg once a week, and then the maintenance dose will be increased up to 240 mg once a week. did.

Diagnosis of CMV retinitis In a patient with immunodeficiency, the retinitis image characteristic of CMV (exudation spots, hemorrhagic spots, vasculitis, vitiligo, etc.) is confirmed by precision fundus examination, and CMV is detected by the following virological examination. The diagnosed case was diagnosed with CMV retinitis. Before starting the initial administration, every week from the first week after the administration to the end of the administration, and at the second week after the termination of the administration, the efficacy of TI-23 was judged mainly by fundus findings.

Detection of CMV antigenemia (virological test
Method ) Van der Bij et al. [Comparison between viremia a
nd antigenemia for detection of cytomegalovirus in
blood, Journal of Clinical Microbiology, 26 (12),
2531-2535, 1988]. That is, blood was collected on the same day as the diagnosis of CMV retinitis, leukocytes were separated from EDTA blood using dextran, cytospin-fixed with acetone, and a monoclonal antibody (C10 + C11) that recognizes the CMV P65 antigen was reacted to perform indirect immunization. A case in which white blood cells with stained nuclei were detected by the peroxidase method and were detected microscopically were regarded as positive for CMV antigenemia.

Detection of CMV in urine (virological test) Shell vial method [Kenji Konno et al., Rapid diagnosis of cytomegalovirus infection by Micro Track method, clinical and virus reprinting, 17 (1), 89-95, 1989] It was measured at. On the same day as the examination of the above items, 3 ml of urine was collected, added to the cells monolayer-cultured in a shell vial, and cultured for 48 hours. afterwards,
The number of viruses contained in 1 ml of urine was measured by the fluorescent antibody method using a monoclonal antibody against the CMV initial antigen.

Immunological test Lymphocyte subset T ₄ · T ₈ , lymphocyte blastogenic reaction by PHA, NK activity, CMV antibody titer and CMV neutralization titer before initiation of initial administration and every 2 weeks after initiation of initial administration. The test was conducted up to 2 weeks after the end of administration.

Measurement of blood anti-regavirumab antibody concentration Two weeks after the administration of TI-23, the anti-regavirumab antibody concentration in the immobilized serum was measured by the sandwich ELISA method using biotinylated regavirumab.

Overall evaluation (1) Overall improvement degree Improvement degree of fundus finding (reduction of 75% or more is markedly improved, 50
Improvement of ~ 75%, improvement of 25 to 50%, improvement of 0 to 25%, deterioration of increase in inflammation) and other ophthalmological findings (visual acuity, vitreous opacity, Field of view),
It was judged comprehensively from subjective symptoms, virological tests and immunological tests, and judged according to the following 5 stages. Significant improvement Somewhat improved No change
Aggravation

(2) Overall Safety Level The following three grades were evaluated according to the content and degree of side effects and abnormal laboratory test values. There is no problem in safety (no side effects) Almost no problem in safety (continuation of administration is possible due to mild side effects) There is a problem in safety (discontinuation of administration due to side effects)

(3) Usability In consideration of the overall degree of improvement and the general safety level, the following three levels were evaluated. Very useful Useful Not very useful Not desirable

[Example 1] International Publication No. 87/03602
Human type monoclonal antibody obtained by the method described in the specification, regavirumab 0.2 part by weight, aminoacetic acid 2 parts by weight, human serum albumin 0.2 part by weight, sodium chloride 0.9 part by weight, distilled water 96. A solution having a composition of 7 parts by weight is prepared, and after aseptic filtration, aseptically dispensed in 20 ml portions into glass vials, freeze-dried, and 40 mg per vial.
A lyophilized product of Regavirumab was obtained.

Example 2 CMV with various underlying diseases
After intravenous administration of TI-23 to 10 patients with retinitis according to the above procedure, various tests other than the above items were performed at a predetermined time, and observed by the investigator before and after the administration. In addition to ophthalmological findings, virological findings, and immunological tests, clinical tests, serum regavirumab concentration, anti-regavirumab antibody concentration, and side effects were comprehensively judged, and comprehensive evaluation was performed according to the method described above. The results are shown in Tables 1 to 4 for each evaluation item. Table 2 shows the overall degree of improvement for each underlying disease (invariant or higher is considered effective and the number of effective cases is the number of cases). For reference, examples (8 cases) in which ganciclovir was used in combination are also shown. The case of combined use with ganciclovir was a dose-reduced case due to ganciclovir ineffectiveness or insufficient effect and side effects.

The serum concentration of regavirumab was 90.1 ± 38.4 μg / ml, and no anti-regavirumab antibody was detected at the end of administration. The anti-regavirumab antibody did not appear after the end of administration, even in the case where the administration was continued for a long period of about one and a half years after the end of this clinical trial. In addition, side effects (2 cases in Table 3)
Was a transient mild fever of unknown causal relationship and could be continuously administered without treatment.

[0029]

[Table 1]

[0030]

[Table 2]

[0031]

[Table 3]

[0032]

[Table 4]

In this way, if invariant or more is valid, TI
The efficacy rate of -23 was 90% alone and 94.4% (17/18) including the combination of ganciclovir.
U. [DICP, The Annals of Pharmacotherapy 23, 5-12
(1989)] effective rate of ganciclovir 86%
It shows an effect equal to or higher than that of (119/138) (Tables 1 and 2), has few side effects, is mild, can be continuously administered, and is highly safe (Tables 3 and 4). In addition, continuous administration is possible in that no antibody to regavirumab appears.

Claims (4)

[Claims] 1. A preventive or therapeutic agent for CMV retinitis, which comprises an anti-CMV human monoclonal antibody that recognizes a cytomegalovirus (CMV) envelope glycoprotein and neutralizes CMV as an active ingredient. 2. The envelope glycoprotein of CMV is Glycopro
The preventive or therapeutic agent for CMV retinitis according to claim 1, which is tein B. 3. The anti-CMV human monoclonal antibody is I
The preventive or therapeutic agent for CMV retinitis according to claim 1 or 2, which is a gG1 antibody. 4. The C according to claim 1, wherein the anti-CMV human monoclonal antibody is regavirumab.
A preventive or therapeutic agent for MV retinitis.