FR2763072A1 - USE OF A MONOCLONAL ANTI-LFA1 ANTIBODY IN RENAL TRANSPLANTATION - Google Patents

Abstract

The invention concerns the use of a monoclonal antibody directed against the human LFA1 molecule for preparing a medicine to reduce initial alteration of the renal function of high-risk organ recipients.

Description

- 1 - The present invention relates to the field of transplantation.

  More particularly, the present invention relates to the use of a monoclonal antibody against the human LFA 1 molecule in a patient receiving a renal transplant. The use of a monoclonal antibody directed against the human LFA 1 molecule for the preparation of an immunosuppressant intended to prevent rejection in a patient is already known in the prior state, and in particular in patent application WO 94/16728. kidney transplant recipient. The success of a kidney transplant is of course linked to the absence of rejection of the organ by the recipient, but also depends on the more or less rapid resumption of graft function in its new host. However, this resumption of function is more or less satisfactory and more or less rapid depending on the conditions under which the transplantation takes place. We know in particular that

  An important part of the success of a kidney transplant is the quality of the organ transplanted.

  Among the parameters involved in this quality, we can cite the age of the organ donor as well as the duration of cold and lukewarm ischemia suffered by the organ between explantation of the donor and implantation in the recipient, the most favorable conditions being those where the donor is young and where cold and lukewarm ischemia has been

short.

  Indeed, the statistical studies carried out on the transplants carried out (Cf.

  notably chapter 1 "The Unos Scientific Renal Transplant Registry, Clinical Transplants 1995, Cecka and Terasaki, Eds. UCLA Tissue Typing Laboratory, Los Angeles, California) have shown that among patients receiving kidneys from elderly donors or kidneys who have been subjected at a fairly long ischemia, the frequency of occurrence of a phenomenon called "delayed graft function" (or DGF for delayed-graft function) and assessed by the need to dialyze the patient during the first week after transplantation, was However, it is known that the more this phenomenon of delayed graft function appears, the less the long-term outcome of the transplant is favorable; this is even clearer if this phenomenon of delayed graft function is associated with an episode acute rejection of

the transplant.

  Thus, to obtain the maximum chances of success in the long term of a renal transplant, it would be necessary to transplant only organs considered as not risking

  lead to delayed graft function.

  -2- However, given the number of patients awaiting a transplant and the small number of available organs satisfying all the criteria for ensuring the long-term success of a transplant, it is desirable to be able to have means for reducing or eliminating the risk introduced when

  uses bodies considered non-preferential.

  It is the object of the invention which, for this purpose, relates to the use of a monoclonal antibody directed against the human LFA 1 molecule for the manufacture of a medicament intended to reduce the initial impairment of function patients renal

  organ recipients at increased risk.

  Thus, the handicap brought by these "marginal" organs is eliminated, which allows, by increasing the number of kidneys available for transplant, to increase on the one hand the total number of possible transplants and on the other hand to increase the chances of

  tissue compatibility between the recipient and the grafted organ.

  The invention will be better understood on reading the description which follows in

reference to figures.

  Figure 1 illustrates the percentage of patients with delayed graft function,

  depending on the age of the donor in years.

  Figure 2 illustrates the percentage of patients with delayed graft function

  depending on the duration, in hours, of cold and lukewarm ischemia.

  Figure 3 illustrates the kinetics of the percentage of patients reaching, without recourse to

  dialysis, a serum creatinine threshold of 250 Fimol / l.

  According to the invention, the monoclonal antibody used is an antibody directed against the human LFA 1 molecule (LFA 1: lymphocyte function associated antigen type 1) which is part of the leukocyte integrins. These integrins are involved in the mechanisms of intercellular adhesion between leukocytes and other cells in a non-specific manner; they are heterodimers all formed from a chain 13 of kDa which is common to them (CD 18) and from a chain a specific to each of them: CD I 1 a for the molecule LFA 1, CD 11 b for the mac molecule

  CD 11 c for the molecule Gp 150.95.

  According to a particular embodiment, the antibody used for the purposes of the invention is an antibody directed against the 180 kDa α chain which is an antigen present on the surface of the cells of the bone marrow of the non-lineage. erythrocyte, T lymphocytes, NK (or Natural Killer) cells, polynuclear leukocytes and monocytes / macrophages. Such an antibody interferes in cell-cell interaction and inhibits in vitro activation of T lymphocytes, NK activity, antibody-dependent cell-mediated cytotoxicity as well as the mixed lymphocyte reaction. It also inhibits

  adhesion of polymorphonuclear cells to human endothelial cells in culture.

  According to a particular characteristic, a monoclonal antibody which is particularly suitable for the purposes of the invention is a mouse monoclonal antibody (IgG 1) composed of two heavy chains of 50 + 5 kDa each and of two light chains

from 25 - 5 kDa each.

  Such an antibody can be obtained by immunization of BALB / c mice using cells originating from a clone of T lymphocytes (Tm 20) which are cytotoxic specific DR2 T cells in the presence of specific HLA class II human molecules. The splenocytes are then recovered from the immunized mice which are

  fuses with murine myeloma cells ATCC CRL 1580-P3X63-Ag8.653.

  The hybridoma obtained can then be cloned. A monoclonal antibody which is particularly suitable for the purposes of the invention is the monoclonal antibody obtained from the hybridoma 25.3.1.19.3B7 deposited in the ECACC collection under the reference

  92,120,309 dated December 3, 1992.

  Any other monoclonal antibody having the same characteristics is also

  likely to be suitable for the purposes of the invention.

  The monoclonal antibody according to the invention can be packaged in injectable form and be presented in this case in aqueous solution also comprising sodium chloride, a surfactant such as polysorbate 80 in the form in particular of Tweenm80, as well as a buffer such than tris (hydroxymethyl) aminomethane. A particularly suitable packaging consists of 5 ml ampoules

  containing 5 mg of monoclonal antibody.

  The administration of the monoclonal antibody is carried out as early as possible during the transplant operation, preferably at least thirty minutes before the resumption of blood circulation in the transplanted graft in the recipient. According to a particular embodiment of the invention, the first administration of the monoclonal antibody is carried out in the recipient, on the day of the transplant.

  as soon as possible after a donor's kidney has been assigned.

  The dose of antibody administered during this first injection is chosen to obtain early saturation of the receptor sites of the LFA 1 molecule. It has been observed that a dose of between 10 and 50 mg, and more particularly approximately

mg, was suitable for this purpose.

  The administration of the antibody is then continued in order to substantially maintain this saturation; however, the doses administered as a result of this first loading dose can be reduced, in particular by half in the case where the administration continues on a daily basis. Preferably, the second dose is administered between 8 and 24 hours after the first dose, then the following doses are administered every 24 hours. Treatment can be continued for up to 30 days. However, we have already obtained very good results in

  continuing treatment only until the tenth day after transplantation.

  According to one embodiment of the invention, the monoclonal antibody is administered at one time by peripheral intravenous route. To this end, the antibody is diluted in an aqueous saline solution or in a dextrose solution. The flow

  administration is calculated so that the duration of the injection is approximately 30 minutes.

  The administration of the monoclonal antibody according to the invention can be carried out in combination with the immunosuppressants conventionally used in the context of a renal transplant, and in particular in combination with cyclosporine, azathioprine, prednisone, tacrolimus , mycophenolate mofetil or any common combination of some of them. However, in a particularly advantageous manner, since the monoclonal antibody according to the invention itself has the property of preventing rejection, it is possible to significantly reduce the number or quantity administered of the immunosuppressants usually prescribed. It was thus possible to successfully postpone the administration of cyclosporine to the tenth day after transplantation. The antifungal, antibiotic and antiviral treatments usually prescribed are entirely compatible with the administration of the monoclonal antibody according to the invention. According to the invention, the monoclonal antibody directed against the human LFA 1 molecule is indicated for reducing the initial impairment of renal function. By reduction in the initial impairment of renal function is meant in particular a reduction in the incidence and / or severity of the delayed graft function, also called DGF for "delayed-graft function", or a shorter duration so that the serum creatinine level of the recipient of the graft reaches a threshold value reflecting a satisfactory recovery of renal function, without having to resort to dialysis. Any other criterion recognized as making it possible to really assess renal function can

  also be used for the purposes of the present invention.

  The delayed function of the graft or DGF is appreciated in different ways in the literature: volume of urine, need for dialysis during the first or the first two week (s) after transplantation. A definition of the delayed graft function used to define the present invention is the need for dialysis during the first week following transplantation with the exception of the need for a single dialysis in the first 24 hours; the need for dialysis in the 24 hours postoperative may indeed result from the pre or perioperative status of the

  patient and not be a good indicator of the condition of the transplanted organ.

  Kidney function is also assessed by the patient's serum creatinine level (or calculated creatinine clearance) in the days and even months after the transplant. For the purposes of the invention, it can be considered that the initial impairment of renal function is reduced when the number of patients rapidly increases, without resorting to dialysis, to a serum creatinine level previously fixed, for example 300 limol / l, or 250 itmol / l, or 180 ptmol / l. It is also possible to assess this reduction by different calculations; one can, in particular, consider that the initial alteration is reduced when, on average, for a patient, the time necessary to reach after transplantation, and without recourse

  on dialysis, a previously fixed serum creatinine threshold is reduced.

  According to one characteristic of the invention, the monoclonal antibody directed against the human LFA I molecule is in particular capable of reducing the initial deterioration of the renal function of patients receiving an organ considered "at increased risk". By organ with "increased risk", for the purposes of defining the invention, an organ having a fairly high probability of leading to the phenomenon of delayed graft function is considered. We were able to identify that organs meeting this definition

  are those from elderly donors or those with prolonged ischemia.

  -6- The curves in Figures 1 and 2 illustrate the results obtained comparatively, with or without the use of the monoclonal antibody, and indicate the percentage of patients who have been subject to the phenomenon of delayed graft function (defined as the need for dialysis during the first week after transplantation) as a function of the donor's age (expressed in years) for Figure 1, and as a function of time

  ischemia (expressed in hours) for Figure 2.

  The results obtained show that the use of the monoclonal antibody according to the invention makes it possible to significantly reduce the incidence of the delayed function of the

  transplant when the donor is old or when the duration of ischemia is extended.

  Obviously, in the case where an organ combines the two risk factors, that is to say come from an elderly donor and have also suffered a prolonged ischemia,

  the use of the monoclonal antibody according to the invention would also be advantageous.

  Thus, thanks to this new use of the antibody according to the invention, it is possible to compensate, with regard to the phenomenon of the initial alteration of the renal function of the graft, the risk incurred by the fact of transplanting an organ of "lower quality". The examples which follow illustrate, without limitation, embodiments

of the present invention.

Example

  A randomized, multicenter open clinical study is carried out on two groups of patients, one of the groups of patients receiving, as the main immunosuppressant, during the 10 days following transplantation, the monoclonal antibody according to the invention, introduction of cyclosporine being delayed until the ninth day, and

  the other group receiving cyclosporine from the day of transplantation.

  The patients studied are recipients of a first cadaver kidney transplant.

  The age of the patients is between 18 and 65 years; the age of the donors is understood

  between 10 and 65 years old. The duration of ischemia is in all cases less than 48 hours.

  -7- The control group consists of 153 patients who are administered: - cyclosporine A at a rate of 8 mg / kg on the day of transplantation (D)

oral, preoperatively.

  After this first dose of 8 mg / kg, the administered dose is adjusted according to the usual criteria of the transplant center. Administration is performed 1

or twice a day.

  In the case of patients who cannot support oral administration, cyclosporine is injected for the first 3 days intravenously, at a rate of 3 mg / kg / day; in this case it is diluted in 20 to 100 ml of a 0.9% sodium chloride solution or in a 5% dextrose solution, and injected very slowly for

  approximately 24 hours, treatment starting 4 to 8 hours before transplantation.

  As soon as possible, a transfer to the oral route is made, the dose

  administered then being adjusted according to the usual criteria of the center.

  - azathioprine 1.5 to 2 mg / kg / day, starting on the day of

transplant (D,).

  Azathioprine is administered orally, once a day, or if

  this is necessary, intravenously.

  - steroids administered at doses and according to the techniques usually used. The test group consists of 148 patients who are administered - azathioprine in the same way as in the control group, - steroids in the same way as in the control group, an anti-alpha monoclonal antibody to the molecule Human LFA 1 produced by hybridoma 25.3.1.19.3B7, at a loading dose of 30 mg on the day of transplantation (D,) then daily maintenance doses of 15 mg during

  9 following days, i.e. until D10.

  The monoclonal antibody is packaged in a 5 ml vial containing: anti-LFA 1 antibody 5 mg * tris (hydroxymethyl) aminomethane 12.1 mg * sodium chloride 43.5 mg * TweenTM 80 1 mg * water for injection qsp 5 ml The dose of antibody to be administered is diluted in 50 to 100 ml of 0.9% sodium chloride solution or 5% dextrose solution, and injected into

  a peripheral vein for 30 minutes.

  -8- The first dose of antibody is administered at the time or in the two hours preceding anesthesia, and in any case at least half an hour before restoring blood circulation in the kidney. The following doses are administered at 1 day

  interval (between 8 and 28 hours after the previous injection).

  - from the ninth day (D9), cyclosporine by the oral route, at a rate of 8 mg / kg / day, or if the patient does not support the oral route, intravenously at the rate this time of 3 mg / kg / day; the frequency of administration and the choice of subsequent doses are determined as mentioned for

patients in the control group.

  In each group, from the thirtieth day (D30), the immunosuppressive treatment implemented is that usually used in the center of

  transplant and is identical for both groups.

  Likewise, the infection control treatments are those usually used by each transplant center and are identical for the two groups. The distribution of patients according to the criteria of sex, age, weight, duration of ischemia, sex and age of the donor is roughly equal in each of the groups. During this study, we are particularly interested in the following parameters - rejection episodes, - patient overweight, - graft survival, - graft function appreciated in particular by the serum creatinine level, - delayed graft function appreciated by the whether or not dialysis is required between D2 and D7. -9- The results obtained at three months with regard to patient survival and graft survival are shown in Table 1 below: ____ Control Group Test Group

149/153 142/148

Patient survival 149/153 142/148

____________ (97%) (96%)

  Transplant survival Survival of the graft 137/153 132/148

_ __ __ ___ __ _ _ (90%) (89%)

  Table 1 It can be seen that the administration of the monoclonal antibody according to the invention makes it possible to obtain, in terms of survival, results as good as conventional administration.

cyclosporine.

  The number of patients who fully followed the protocol planned for the clinical study is one hundred and fifty two for the control group and one hundred and thirty two for the

test group.

  Among these patients constituting what will be called hereinafter the total population, two subpopulations are defined: organ recipients who have had ischemia for more than 24 hours or who have come from a donor aged

over 50 years.

  - the "standard" subgroup, consisting of patients receiving an organ having undergone ischemia for less than 24 hours and coming from a donor aged

under 50.

- 10 -

  The results relating to the phenomenon of acute rejection for each of the populations defined above are expressed in table 2 below, which indicates at three months the

  number of patients who had at least one acute rejection.

  Control group Test group Total population 56/152 49/132

_____ _____ ___ (37%) (37%)

Population "at risk" 32/79 22/69

(41%) (32%)

"Standard" population 24/73 27/63

(33%) (43%)

Table 2

  These results show that if, overall, the risk of acute rejection is roughly the same regardless of the treatment method used, on the other hand, if we consider the population "at risk" with regard to the initial impairment of renal function, the administration of a monoclonal antibody according to the invention makes it possible to decrease

  the incidence of acute rejection.

  The results relating to the incidence of delayed graft function are expressed in Table 3, which indicate, for each population, the number of patients having

  been subjected to dialysis between D2 and D7.

  Control group Test group Total population 50/152 33/132

(33%) (25%)

Population "at risk" 34/79 21/69

(43%) (30%)

  "Standard" population 16/73 12/63 t ________________ (22%) (19%)

Table 3

- 11 -

  These results show that the incidence of delayed graft function is reduced in patients to whom the monoclonal antibody according to the invention is administered; this reduction is particularly marked in patients considered "at risk" (more than

  % in relative value), which was totally unexpected.

  The results relating to the number of patients who, at three months, experienced both an acute rejection phenomenon and a delayed graft function phenomenon, are shown in table 4 below: Control group Test group Total population 19 / 152 9/132

(13%) (7%)

Population "at risk" 14/79 6/69

(18%) (9%)

/ 73 3/63

"Standard" population 3/63

(7%) (5%)

Table 4

  Once again, the results obtained here show the same tendency, that is to say that the administration of the monoclonal antibody according to the invention is particularly advantageous for patients receiving an organ considered "at risk" which are those in which the frequency of occurrence of the two phenomena combined is greater, when the immunosuppression protocol used is a protocol of the prior art. However, the combined appearance in the same patient of these two phenomena has been considered to limit the chances of long-term survival of a kidney transplant. Also, thanks to the use of the monoclonal antibody according to the invention, it is believed to be able to increase the chances of long-term survival of

the transplanted organ.

  - 12- The results relating to early renal function, expressed as a percentage of patients who, at three months, reached, at least once, without dialysis aid, a serum creatinine level of less than 250 rmol / l, are shown in table 5 below Control group Test group Total population 88% 92% "At risk" population 82% 90% "Standard" population 93% 95%

Table 5

  Similarly, if we assess early renal function by the average time (in days) taken by a patient to reach a serum creatinine level of 250 Fimol / l, we obtain the results indicated in Table 6 below: Control Group Test Group Total population 14.7 12.3 "At risk" population 18.4 13.4 "Standard" population 11.1 11.1

Table 6

  These results illustrate the reduction, thanks to the invention, of the initial impairment of renal function in patients receiving a kidney from a donor over the age of

  years or having suffered ischemia for more than 24 hours.

  - 13- Tables 7 and 8 illustrate, in parallel to Tables 5 and 6, the results obtained when, instead of considering a threshold serum creatinine value of

  250 pmol / l, a threshold value of 180 pmol / l is considered.

  Percentage of patients reaching threshold at Group Control Group Test three months Total population 80% 83% "At risk" population 73% 80% "Standard" population 86% 86%

Table 7

  Average duration in days Control group Test group to reach threshold Total population 19.6 15.8 "At risk" population 26.4 16.4 "Standard" population 13.3 15.1 Table 8 Here again, we note that according to the he invention, the initial impairment of renal function is reduced, in particular, in patients receiving an organ considered "at risk". When we follow, for patients receiving an organ considered "at risk", the serum creatinine level over time and, as we plot for each of the two groups (control and test), the kinetic curve of the percentage of patients having reached a rate of 250 imol / l without resorting to dialysis, it is noted, as is illustrated in FIG. 3, that the results obtained are better for the patients belonging to the test group. Indeed, thanks to the administration of the monoclonal antibody according to the invention, the initial impairment of renal function is reduced, which allows the

  transplant patient to recover a functional organ faster.

- 14-

Claims (8)

Claims   1. Use of a monoclonal antibody directed against the human LFA 1 molecule for the manufacture of a medicament intended to reduce the initial deterioration of the renal function of patients receiving an organ at increased risk. 2. Use according to claim 1, characterized in that the organ at increased risk   consists of an organ removed from a donor of advanced age.   3. Use according to one of claims 1 or 2, characterized in that the member to   increased risk consists of an organ removed from a donor aged 50 or more.   4. Use according to one of the preceding claims, characterized in that   the organ at increased risk is an organ that has suffered prolonged ischemia.   5. Use according to one of the preceding claims, characterized in that   the organ at increased risk is an organ that has suffered ischemia duration greater than 24 hours.   6. Use according to one of the preceding claims, characterized in that   the monoclonal antibody is directed against the ot subunit of the human LFA 1 molecule.   7. Use according to one of the preceding claims, characterized in that the   reduction in the initial impairment of renal function is assessed by the time required for patients to reach, without dialysis, a serum creatinine level less than or equal to 250 jimol / l.   8. Use according to one of the preceding claims, characterized in that the   reduction in the initial impairment of kidney function is appreciated by the reduction in the number of patients having dialysis between the second and the seventh day after the transplant.