Australian haematologists have tracked immunoglobulin replacement therapy (IgRT) use in chronic lymphocytic leukaemia (CLL) patients after finding blood cancer-related hypogammaglobulinaemia consumes most of the country’s ‘valuable resource’.
A review of Lifeblood’s databases revealed nearly 1.5 million grams of IVIg went to 2.7 thousand CLL patients in 2008 to 2013, in a bid to treat hypogammaglobulinaemia and severe and/or recurrent infection.
The often elderly, male patients with pretreatment IgG levels of 4.03 g/L ± 2.03 underwent 48,870 treatment episodes over the study period, a number fuelled by a 5.5% increase in CLL IVIg demand per year, Dr Anastazia Keegan, consultant haematologist and transfusion medicine specialist at Australian Red Cross Lifeblood, and her team reported in the European Journal of Haematology.
Most (90%) patients received domestically-produced Intragam P, while the rest accessed imported products such as Octagam 5% and 10%, Kiovig10%, Flebogamma 5% DIF and Sandoglobulin NF.
Overall IVIg demand has been increasing for decades and will only continue to, as the population grows, ages, accumulates diagnoses and expects higher standards of healthcare, Dr Keegan and her team wrote.
This trend “will need to be factored into [immunoglobulin replacement therapy] supply and budgets,” they noted.
In the 2000s, the National Blood Authority (NBA) worked to improve IVIg access by allowing international manufacturers to supplement domestic products. They also developed the Criteria for the clinical use of intravenous immunoglobulin in Australia — which support “the therapeutic use of IVIg for a range of neurological, immunological and haematological conditions requiring immune modulation or immune replacement that would be approved and therefore, funded by the NBA Agreement”.
However, IVIg is still a “relatively scarce” blood product and studies such as this aim to help “Australian, and international, healthcare sectors to understand the demographic characteristics and geographical distribution of patients to ensure adequate ongoing supply and good stewardship of this valuable resource,” the authors wrote.
Beyond supply and demand, good stewardship is critical for managing and justifying the high cost of IVIg.
“IVIg is an expensive therapy costing between $AUS54–78 per gram and given the often protracted dosing regimens required for IgRT in haematological malignancies including CLL, the total annual cost for this therapeutic blood product is considerable,” the authors wrote.
In 2011–12, CLL patients accessed 243,972 grams of IVIg, costing them, on average, AUS$5,578 each, they reported.
However, the cost is “comparable with a single hospital admission via the Emergency Department in NSW ($7,557), a single day in an Intensive Care Unit (ICU) bed (~$4375), or 6 months of fludarabine in 2011 ($6708) and significantly less than adding rituximab to fludarabine plus cyclophosphamide (FC+R) in 2009 (incremental +R cost $40,268)”.
It’s also a fraction of the cost of current targeted therapies, where ibrutinib is $105,528 per annum and venetoclax is $93,410 per annum.
“Hence, the cost of ongoing IgRT/IVIg is offset if it prevents a single hospital admission via Emergency, or >1 day in an ICU bed each year,” Dr Keegan and her team suggested.
Even if clinicians and patients can justify the expense, adverse side effects associated with IVIg may prevent the drug’s ubiquitous use in CLL.
Additionally, they’ll have to consider IVIg’s usefulness, where the drug has been shown to reduce bacterial infections, and dosage, where a consensus on optimal dosage and frequency has yet to be reached.
The authors hope that a deeper understanding of supply, demand, use and cost will help haematologists, guideline authors, IVIg manufacturers and suppliers appropriately manage the drug’s use and ensure ongoing access for patients.