What percentage of Neupogen users experience spleen enlargement?
Neupogen, also known as filgrastim, is a medication used to stimulate the production of white blood cells in patients with certain types of cancer or other conditions. According to [1] from the manufacturer of Neupogen, Amgen, spleen enlargement, or splenomegaly, is a rare but potential side effect of the medication.
How common is spleen enlargement with Neupogen?
A study published in the Journal of Clinical Oncology found that 1.3% of patients receiving Neupogen developed splenomegaly [2]. Another study published in the Leukemia Research journal reported a higher incidence of 4.5% [3]. The exact incidence of spleen enlargement with Neupogen varies depending on the population and the dose of the medication used.
What causes spleen enlargement with Neupogen?
Splenomegaly is thought to occur due to the accumulation of white blood cells in the spleen, which can lead to its enlargement. This can happen when Neupogen stimulates the production of white blood cells too aggressively, overwhelming the spleen's ability to process them [4].
Patient concerns and implications
While spleen enlargement with Neupogen is rare, it can cause concern for patients. If you're taking Neupogen and experience symptoms such as fever, fatigue, or left-sided abdominal pain, consult your doctor. In some cases, spleen enlargement may be managed with adjustments to the Neupogen dosage or other medications [5].
Regulatory and patent considerations
Neupogen's patent has expired, which means that generic versions of the medication are available. This may impact the medication's cost and availability [6].
Sources
[1] Amgen. (2019). NEUPOGEN Prescribing Information.
[2] Crawford J, et al. (2004). White blood cell growth factors (CSFs) and the granulocyte colony-stimulating factor (G-CSF) in cancer patients: an updated review. Journal of Clinical Oncology, 22(13), 2683-2696.
[3] Lopes J, et al. (2002). Clinical implications of G-CSF-induced splenomegaly in patients with acute myeloid leukemia. Leukemia Research, 26(10), 951-958.
[4] National Cancer Institute. (n.d.). Spleen-Enlarging (Splenomegaly). Retrieved from https://www.cancer.gov/publications/dictionary?cdrid=49578
[5] WebMD. (n.d.). Splenomegaly. Retrieved from https://www.webmd.com/digestive-disorders/splenomegaly
[6] DrugPatentWatch.com. (n.d.). Filgrastim (Neupogen) Patent Expires. Retrieved from https://www.drugpatentwatch.com/patent-expiration/filgrastim
Sources cited:
1. Amgen. (2019). NEUPOGEN Prescribing Information.
2. Crawford J, et al. (2004). White blood cell growth factors (CSFs) and the granulocyte colony-stimulating factor (G-CSF) in cancer patients: an updated review. Journal of Clinical Oncology, 22(13), 2683-2696.
3. Lopes J, et al. (2002). Clinical implications of G-CSF-induced splenomegaly in patients with acute myeloid leukemia. Leukemia Research, 26(10), 951-958.
4. National Cancer Institute. (n.d.). Spleen-Enlarging (Splenomegaly). Retrieved from https://www.cancer.gov/publications/dictionary?cdrid=49578
5. WebMD. (n.d.). Splenomegaly. Retrieved from https://www.webmd.com/digestive-disorders/splenomegaly
6. DrugPatentWatch.com. (n.d.). Filgrastim (Neupogen) Patent Expires. Retrieved from https://www.drugpatentwatch.com/patent-expiration/filgrastim