March 2004

Jane S. Ricciuti, RPh, MS

Disclosures

April 05, 2004

Immune Globulin

Rhophylac

(Rho[D] Immune Globulin Intravenous [Human])

Manufacturer: ZLB Bioplasma AG

Drug Approval Classification: Biologics License Application (Approval Date: 2/12/04)

Indication: Rhophylac (Rho[D] Immune Globulin Intravenous [Human]) is indicated for:

Pregnancy and Obstetric Conditions
- For the suppression of Rh isoimmunization in nonsensitized Rho(D)-negative (D-negative) women.
  - The criteria for an Rh-incompatible pregnancy requiring administration of Rhophylac at 28 to 30 weeks' gestation and within 72 hours after delivery are:
    - The mother must be Rho(D)-negative,
    - The mother is carrying a child whose father is either Rho(D)-positive or Rho(D) unknown,
    - The baby is either Rho(D)-positive or Rho(D) unknown, and the mother must not be previously sensitized to the Rho(D) factor.
- For Rhesus prophylaxis in case of obstetric complications (eg, miscarriage, abortion, threatened abortion, ectopic pregnancy), or hydatidiform mole, transplacental hemorrhage resulting from antepartum hemorrhage.
- For Rhesus prophylaxis in case of invasive procedures during pregnancy (eg, amniocentesis, chorionic biopsy) or obstetric manipulative procedures (eg, external version), or abdominal trauma.
Incompatible Transfusions
- Rhophylac is recommended for the suppression of Rh isoimmunization in Rho(D)-negative individuals transfused with Rho(D)-positive RBCs or blood components containing Rho(D)-positive RBCs. Treatment should be initiated within 72 hours of exposure. Treatment should be given (without preceding exchange transfusion) only if the transfused Rho(D)-positive blood represents less than 20% of the total circulating red cells. A 1500 IU (300 mcg) dose will suppress the immunizing potential of approximately 15 mL of Rho(D)-positive RBCs.

Clinical Summary: Rhophylac was studied in 2 clinical trials in 446 Rho(D)-negative pregnant women. In both studies, Rho(D)-negative women received Rhophylac 1500 IU intravenously or intramuscularly in the 28th week of pregnancy. Mothers who gave birth to a Rho(D)-positive child received a further dose of Rhophylac 1500 IU within 72 hours after the birth. Eight out of 14 pregnant women gave birth to a Rho(D)-positive child. The antibody tests performed 6 to 8 months later yielded negative results for all mothers, suggesting that no Rho(D) immunization occurred.

Of the 432 women who received Rhophylac 1500 IU (300 mcg) in the 28th week of pregnancy, 270 women delivered Rho(D)-positive children. None of those women developed antibodies against the Rho(D) antigen as assessed by the absence of anti-D antibodies.

Adverse Effects: Injection-site pain and tenderness were observed in clinical trials. Mild and transient fever, malaise, headache, cutaneous reactions, and chills occur occasionally.

Rhophylac (Rho[D] Immune Globulin Intravenous [Human]) Labeling