Cytoreductive therapy in younger adults with polycythemia vera: a meta-analysis of safety and outcomes

[Manouche]

 »To our knowledge, this is the first systematic review and meta-analysis evaluating the available evidence regarding the safety of cytoreductive agents in PV<60. Our findings suggest that both rIFN-α and HU are safe and well-tolerated in younger patients with low rates of discontinuation for toxicity. The annualized rates of discontinuation we calculated are similar to those reported for older patients who are routinely prescribed cytoreductive therapy. In fact, our institutional experience showed even lower rates of discontinuation at 2.2% and 2.8% for HU and rIFN-α, respectively, a finding possibly related to younger age of our patients, dosing, or longer follow-up. With regards to efficacy, nearly all PV<60 patients achieved a hematologic response (CHR + PHR of 90%-95%) with both rIFN-α and HU; a proportion at least as good as reported for older patients or “high-risk” patients with PV »

ashpublications.org/bloodad...

[EPguy]

Notable observation:

"PV<60 patients suffer greater risk of disease progression to sMF than thrombosis during a few years of follow-up"

This was with cytoreduction (IFN or HU). This seems to be new info.

They found both HU and IFN were effective with IFN having somewhat better outcomes:

For IFN and HU: thrombotic events ... annual rate of 0.79% and 1.26%; secondary myelofibrosis at 1.06% and 1.62%; acute myeloid leukemia at 0.14% and 0.26%; and death at 0.87% and 2.65%".

Rux was not included.

They acknowledge the data are limited and not always comparable.

[cata]

Hello Manouche , I don t know what means “nearly all PV<60 patients achieved a hematologic response (CHR + PHR of 90%-95%) with both rIFN-α and HU;”îs posibile to explain in a language more accesibile to me ego do not know these medical abbreviations ? Thank you for your post and future explanations

Regards

Cata

[Manouche in reply to cata]

Hi cata,

CHR and PHR stand for Complete Haematological Response and Partial Haematological Response.

[ainslie]

Manouche

To clarify, you said nearly all patients achieved a haematological response, looking at the paper doesn’t it say 62% on inf achieved CHR and something like 50+% on HU achieved CHR.

Interesting paper though ,thanks for posting it.

[Manouche in reply to ainslie]

It says that with both HU and interferon, PV<60 patients achieved a hematologic response (CHR + PHR of 90%-95%).

[ainslie in reply to Manouche]

yes CHR+PHR was 90-95% but CHR was about 62 and 50, PHR means they had some change in counts but it doesnt mean very much ie an improvement in counts but not in necessarily range as far as I know

to be fair to you you did say CHR+PHR was 90-95%, which could be a bit misleading to those who dont know what PHR means, splitting out the CHR and PHR maybe gives a clearer picture

[Manouche in reply to ainslie]

PHR is a positive outcome. It’s your right to believe that it doesn’t mean very much. IMO, most of us would be satisfied to get any positive outcome at some point.

[ainslie in reply to Manouche]

Of course any improvement is better than nothing but certain counts need to be in range, reds need to be in range to reduce thrombotic risk with PV and whites should be nearly in range for same reason and platelets are less important unless symptomatic or other risk issues.

[DougyW]

It would be great to get a long term view of the efficacy wrt transition to worse conditions. And add in AB impacts/ signposting of transition. That would answer some important questions.