What is the role of hydroxyurea in variant sickle cell genotypes?

I have had little success using hydroxyurea in my patients with hgb SC disease and at this point in patients with two or more acute visits over 12 months for pain, I am using crizanlizumab as some of the subjects in the phase 2 study on which the drug received FDA approval had SC disease (Ataga et al., PMID 27959701).

For those with Sb+thal, I will try hydroxyurea as first-line therapy in patients who meet the NHLBI guideline recommendations for the use of HU (3 or more crises in 12 months, chron...

My success with hydroxyurea in patients with HbSC disease has been variable. Some have had excellent responses and have become advocates for hydroxyurea with their peers. Others have not responded. So my approach is to offer a 6 months-1 year trial to patients with this genotype. I do counsel them about the lack of randomized evidence upfront and do offer them crizanlizumab as an alternative.