HyperRHO® S/D [RhO (D) Immune Globulin (Human)]
for prevention of Rh hemolytic disease of the newborn (HDN)

HyperRHO® S/D for Prevention of Rh Hemolytic Disease of the Newborn (HDN)

Q&A

What is the Rh factor and why is it important during pregnancy?

The Rh factor is an antigen that is found on the surface of red blood cells. If you have these antigens on your red blood cells, you would be considered Rh positive. Those that do not are Rh negative.1

How can the Rh factor affect pregnancies?

Hemolytic disease of the newborn is caused when an Rh-negative woman is carrying an Rh-positive baby. If the father is Rh positive, there is a good chance the baby will be too. If the baby's blood comes into contact with the mother's blood, the mother's immune system will consider it a foreign entity and begin to create antibodies to attack the foreign Rh-positive blood cells. This response is called isoimmunization.1

When is there a risk of blood exchange?

The exchange of blood usually occurs during delivery, but can happen during a miscarriage, amniocentesis, or as a result of an injury or trauma. There have been instances though, where women develop antibodies to Rh-positive blood cells during pregnancy for no apparent reason.1

What happens when a baby is born with HDN?

If a baby is born with HDN, the infant may suffer from jaundice, anemia, or have permanent damage to the brain and central nervous system. These symptoms can lead to mental retardation, hearing loss, or cerebral palsy.1

Is there treatment for HDN?

Extensive medical assistance may be necessary, including an exchange transfusion, which is where the baby's blood is replaced. By transfusing all of the baby's blood, the destruction of its red blood cells should stop, giving the baby a chance to survive.1

Can HDN be prevented?

Yes, prevention is key to protection. HyperRHO S/D is an immune globulin, which if administered properly can prevent hemolytic disease of the newborn, assuming that the mother does not already have Rh-positive antibodies in her system. HyperRHO S/D has high levels of specific antibodies against Rh-positive blood cells. When injected, HyperRHO S/D destroys any Rh-positive red blood cells that may have entered the mother's body. The injection also prevents the mother's immune system from further production of Rh-positive antibodies, hence protecting the baby from contracting hemolytic disease of the newborn.1

When should HyperRHO be administered?

Since laboratory findings have seen the development of Rh-positive antibodies during the final weeks of pregnancy, your doctor will probably suggest a first dose be given at 28 weeks' gestation. HyperRHO S/D should be administered again within 72 hours of delivery of an Rh-positive baby. For women undergoing spontaneous or induced abortion of up to 12 weeks' gestation, HyperRHO S/D Mini-Dose should be administered within 3 hours or as soon as possible following the abortion.1,2

Quick Facts

  • In the United States, the frequency of Rh D-negative status varies from about 17% in Caucasians to about 7% in Hispanics and African Americans. The frequency is much lower in people of Asian descent (including people from China, India, and Japan), averaging about 2%3
  • Once a mother is sensitized, she can no longer receive immune globulin treatment for HDN. This is why it is crucial to have an Rh immune globulin such as HyperRHO S/D administered before the mother is exposed to Rh-positive red blood cells1
  • An Rh-negative woman must be treated with an Rh immune globulin during each pregnancy4
  • If an estimated 4 million births occur each year, approximately 4,000 of those infants will be victims of HDN5

HyperRHO S/D Full Dose and Mini-Dose IMPORTANT SAFETY INFORMATION

WARNINGS

HyperRHO S/D is made from human plasma. Products made from human plasma may contain infectious agents, such as viruses that can cause disease.

PLEASE SEE WARNINGS, PRECAUTIONS, AND ADVERSE REACTIONS IN THE PRESCRIBING INFORMATION. NEVER ADMINISTER HyperRHO S/D FULL DOSE INTRAVENOUSLY. INJECT ONLY INTRAMUSCULARLY. NEVER ADMINISTER TO THE NEONATE.

NEVER ADMINISTER HyperRHO S/D MINI-DOSE INTRAVENOUSLY. INJECT ONLY INTRAMUSCULARLY. ADMINISTER ONLY TO WOMEN POSTABORTION OR POSTMISCARRIAGE OF UP TO 12 WEEKS' GESTATION. NEVER ADMINISTER TO THE NEONATE.

RhO (D) Immune Globulin (Human) should be given with caution to patients with a history of prior systemic allergic reactions following the administration of human immunoglobulin preparations. The attending physician who wishes to administer RhO (D) Immune Globulin (Human) to persons with isolated immunoglobulin A (IgA) deficiency must weigh the benefits of immunization against the potential risks of hypersensitivity reactions. Such persons have increased potential for developing antibodies to IgA and could have anaphylactic reactions to subsequent administration of blood products that contain IgA. As with all preparations administered by the intramuscular route, bleeding complications may be encountered in patients with thrombocytopenia or other bleeding disorders.

PRECAUTIONS

HyperRHO S/D FULL DOSE AND HyperRHO S/D MINI-DOSE:

A large fetomaternal hemorrhage late in pregnancy or following delivery may cause a weak mixed field positive DU test result. If there is any doubt about the mother’s Rh type, she should be given RhO (D) Immune Globulin (Human). A screening test to detect fetal red blood cells may be helpful in such cases. If more than 15 mL of D-positive red blood cells are present in the mother’s circulation, more than a single dose of HyperRHO S/D Full Dose is required. Failure to recognize this may result in the administration of an inadequate dose.

HyperRHO S/D FULL DOSE:

Although systemic reactions to human immunoglobulin preparations are rare, epinephrine should be available for treatment of acute anaphylactic symptoms.

Administration of live virus vaccines (eg, MMR) should be deferred for approximately 3 months after RhO (D) Immune Globulin (Human) administration.

Should be given in pregnant women only if clearly needed because animal reproduction studies have not been conducted.

Safety and efficacy in pediatric patients have not been established.

ADVERSE REACTIONS

HyperRHO S/D FULL DOSE:

Elevated bilirubin levels have been reported in some individuals receiving multiple doses of RhO (D) Immune Globulin (Human) following mismatched transfusions. This is believed to be due to a relatively rapid rate of foreign red cell destruction.

HyperRHO S/D FULL DOSE AND HyperRHO S/D MINI-DOSE:

Reactions to RhO (D) Immune Globulin (Human) are infrequent in RhO (D)-negative individuals and consist primarily of slight soreness at the site of injection and slight temperature elevation. While sensitization to repeated injections of human immunoglobulin is extremely rare, it has occurred.

HyperRHO S/D is made from human plasma. As with all plasma-derived therapeutics, the potential to transmit infectious agents, such as viruses and theoretically, the Creutzfeldt-Jakob (CJD) agent that can cause disease, cannot be totally eliminated. There is also the possibility that unknown infectious agents may be present in such products.

Please refer to the HyperRHO S/D Full Dose Prescribing Information (PDF) for full prescribing details. To print a copy of the PDF, click here.

Please refer to the HyperRHO S/D Mini-Dose Prescribing Information (PDF) for full prescribing details. To print a copy of the PDF, click here.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

References:

  1. HyperRHO S/D Full Dose [package insert]. Research Triangle Park, NC: Grifols; 2007.

  2. HyperRHO S/D Mini-Dose [package insert]. Research Triangle Park, NC: Grifols; 2007.

  3. National Center for Biotechnology Information. Blood groups and red cell antigens. Hemolytic disease of the newborn. http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=rbcantigen&part=ch4. Accessed June 16, 2009.

  4. March of Dimes. professionals and researchers. What's inside. Accessed June 16, 2009.

  5. Mari G, for the Collaborative Group for Doppler Assessment of the Blood Velocity in Anemic Fetuses. Noninvasive diagnosis by Doppler ultrasonography of fetal anemia due to maternal red-cell alloimmunization. New Engl J Med. 2000;342:9-14.