Composition comprising an ige antibody

An IgE antibody for use according to any preceding claim, wherein using immunohistochemical detection of FRα, less than 50%, 30% or 20% of tumor cells in the subject show moderate- or high- (2+) intensity staining for membrane FRα.

An IgE antibody for use according to any preceding claim, wherein tumor cells in the subject are classified according to (i) membrane FRα staining intensity on a scale from 0 (no detectable FRα) to 3 (high FRα) and (ii) percentage of tumor cells positive for FRα (from 0 to 100%);

• and wherein an overall tumor FRα expression score for the subject is determined as the product of (i) and (ii).

An IgE antibody for use according to any preceding claim, wherein tumor FRα expression in the subject is lower than in at least 50% of cancer subjects;

• preferably wherein membrane FRα expression in tumor cells of the subject is lower than in at least 60%, at least 70% or at least 80% of subjects suffering from the same form of cancer;
• more preferably wherein tumor FRα expression in the subject is lower than in at least 50%, at least 70% or at least 90% of FRα-expressing tumors (preferably FRα-expressing ovarian tumors).

An IgE antibody for use according to any preceding claim, wherein the tumor expresses FRα;

• preferably wherein tumor cells in the subject show detectable membrane FRα expression by immunohistochemistry.

An IgE antibody for use according to any preceding claim, wherein at least 1% of tumor cells in the subject show detectable membrane FRα expression using immunohistochemical detection of FRα;

• preferably wherein at least 5%, 10%, 15% or 20% of tumor cells in the subject show detectable membrane FRα expression.

An IgE antibody for use according to any preceding claim, wherein the antibody is a MOv18 IgE antibody.

An IgE antibody for use according to any preceding claim, for use in treating and/or delaying progression of cancer in the subject.

An IgE antibody for use according to any preceding claim, wherein the tumor or cancer is an ovarian tumor or ovarian cancer.

An IgE antibody for use according to any preceding claim, wherein the antibody lacks a cytotoxic moiety, preferably wherein the antibody is not an antibody-drug conjugate (ADC).

An IgE antibody for use according to any preceding claim, wherein a maximum weekly dose of the IgE antibody administered to the subject is 50 mg, 25 mg, 10 mg, 3 mg or 1 mg.

An IgE antibody for use according to any preceding claim, wherein the IgE antibody is administered to the subject once a week or once every two weeks.

An IgE antibody for use according to any preceding claim, wherein the IgE antibody is administered to the subject in a dose per administration of less than 1 mg/kg, less than 0.1 mg/kg or less than 0.03 mg/kg.

An IgE antibody for use according to any preceding claim, wherein the IgE antibody is administered to the subject in a dose of less than 1 mg/kg/week, less than 0.1 mg/kg/week, or less than 0.03 mg/kg/week.

A method for treating and/or delaying progression of cancer in a subject having a low FRα-expressing tumor, the method comprising a step of administering an anti-folate receptor alpha (FRα) immunoglobulin E (IgE) antibody as defined in any preceding claim to the subject in a therapeutically-effective amount.