Back to the Top
Dear all,
I am planning a 2 way crossover steady-state bioavailability study of a
molecule, in which I am going to measure parent compound as well as its
active metabolite. Volunteers will stay for around 6 days with 15 days
washout in between the two periods. As I have to measure two compounds,
time points are somewhat more than usual and so amount of blood. Can
anybody provide some input that, how much maximum amount of blood one
can withdraw in this type of study. Any recommendation from the
guidelines ?
Waiting for the comments..
Dr. Nirav Gandhi (MD)
Back to the Top
hi nirav
i think 285 mL is the cut of volume for blood withdrawal in a study
(both periods) that includes the volume of blood withdrawn for
screening purposes also.
hope this helps
manish
Back to the Top
The following message was posted to: PharmPK
Dr. Nirav Gandhi (MD),
We try to keep the total blood draw for the entire study under
approximately
500 mL (including all screening, study and follow-up labs as well as PK
draws). Include in your exclusion criteria that your subjects haven't
donated any blood within the past 30-60 days which is usually about 500
mL
also. You should be fine, one time I had a 5 period BA study and we
were
just under 500 mL.
Regards.
Rob
Back to the Top
The following message was posted to: PharmPK
Dear Nirav
As per my knowledge, the regulatory agencies don't give any cut-off
volume for blood collection. It is up to the IRB or Ethics committee to
decide on the blood volume, as they are responsible for the safety of
the volunteers. One IRB which i know, based at Delhi generally allow BE
study with a maximum blood loss of around 475 mL. Above this, the
Ethics committee is concerned about the safety of the volunteers.
But in your case as you are planning a 2x2 crossover study, I think
around 300mL of blood loss will not be of any concern.
Thanx
Dr. Tausif Ahmed
Back to the Top
Dear Mr Rob, Dr. Karan, Mr. Tausif & Mr. Manish,
Thank you for your suggestions.
As I am planning a steady state (5 -- 6 days) 2 way crossover BA study,
the blood collection will definitely be more than usual 350ml. As per
my understanding & knowledge, there are certain blood bank & even FDA
guidelines for the blood collection. MR. Rob, can you suggest any
guideline in which they mentioned about the total blood collection of
upto 450 -- 500 ml ? It will help me a lot to justify my study.
Dr. Nirav Gandhi (MD)
Back to the Top
The following message was posted to: PharmPK
Dear Dr. Gandhi,
Following reference would help you in deciding the blood volume in your
steady state study. This is as per the guideline from Protection of
Human
Subjects available online at FOI . However, considering that you will be
using Indian subjects, it is better not to cross 450 ml of blood.(
1unit of
blood)
http://www.hhs.gov/ohrp/humansubjects/guidance/expedited98.htm
I have copied the relevant points for your quick reference..
Collection of blood samples by finger stick, heel stick, ear stick, or
venipuncture as follows:
(a) from healthy, nonpregnant adults who weigh at least 110 pounds. For
these subjects, the amounts drawn may not exceed 550 ml in an 8 week
period
and collection may not occur more frequently than 2 times per week; or
(b) from other adults and children, considering the age, weight, and
health
of the subjects, the collection procedure, the amount of blood to be
collected, and the frequency with which it will be collected. For these
subjects, the amount drawn may not exceed the lesser of 50 ml or 3 ml
per kg
in an 8 week period and collection may not occur more frequently than 2
times per week.
There is a discussion on blood donation available at FDA site..
http://www.fda.gov/CBER/minutes/donsuit120999.htm
Hope this helps.
Regards
M.M. Ganesh
Clinical Pharmacology Unit
Ranbaxy
Tel: 011-29959588
My Web Page: www.geocities.com/ganaish/gans
PharmPK Discussion List Archive Index page
Copyright 1995-2010 David W. A. Bourne (david@boomer.org)