A Randomized, Multi-center, Open-label, Paired Controlled, Crossover In Vivo Study

For each of the 2 study donation periods, this study will have the following procedures:
single or double dose platelet apheresis collection, pathogen inactivation with INTERCEPT
Blood System treatment, storage for 6 or 7 days (depending on the period and randomization
scheme) at 20°C to 24°C with agitation, collection of "fresh" autologous platelets,
radiolabeling, infusion of fresh and stored INTERCEPT Blood System-treated radiolabeled
autologous platelets, and collection of blood samples for assessment of platelet recovery and
survival (lifespan). There will be a minimum wash-out period of two weeks between the two
study periods.

Apheresis platelets will be collected using the Amicus separator and stored for 6 or 7 days
(depending on the period and randomization scheme) in 35% plasma/65% InterSol.

Procedures will be as follows: On Day 0, each healthy volunteer subject has apheresis
platelets collected. INTERCEPT Blood System treatment will begin on either the day of
donation (Day 0) or the day following donation (Day 1) and will be completed within 24 hours
after collection. Platelets will then be stored for 6 or 7 days after collection (depending
on the period and randomization scheme) at 22°C ±2°C with agitation. Aliquots for in vitro
platelet function will be taken on Day 0/1 before INTERCEPT Blood System treatment and on Day
6 or 7. On Day 6 or 7, healthy volunteers will return to the site, and 43 mL of blood will be
drawn into a syringe containing 9 mL of Anticoagulant Citrate Dextrose Solution, Formula A
(ACD-A). Fresh platelets will be prepared from this sample. An aliquot (10-20 mL) of the
stored INTERCEPT Blood System for platelets will be aseptically removed from each subject's
test container.

Previously stored (Test) and fresh (Control) platelets will be radiolabeled according to
randomization assignment with either Chromium-51 (51Cr) (≤20 μCi) as sodium radiochromate
(Na251CrO4) or Indium-111 (111In) (≤15 μCi) as indium oxine, following the labeling and
washing procedures outlined by the Biomedical Excellence for Safer Transfusion (BEST)
Collaborative. The isotope labels will be assigned randomly with equal probability that fresh
platelets and stored INTERCEPT Blood System for platelets will be labeled with each isotope.,
and the same randomization assignment of isotope labels will be utilized for both donation
periods for the same subject. Aliquots of the fresh and stored platelets will be radiolabeled
in tubes with the standard techniques. After radiolabeling, the autologous fresh and stored
INTERCEPT Blood System for platelets will be simultaneously infused into the subject
(approximately 10-30 mL). Negative pregnancy test for females of childbearing potential are
required before infusion.

Blood samples for radioactivity measurements will be drawn immediately before infusion and at
approximately 0, 0.5, 1, and 2 hours post-infusion, and then 6 more samples will be drawn at
1, 2, 3, 4 (or 6), 7, and 11±1 days post-infusion, at approximately the same time of day as
the radiolabeled platelet infusion was administered (±4 hours).

Patients will be monitored for safety (adverse events) from the beginning of the study until
10 days following the infusion of radiolabelled platelets in period 2.

Radioactivity measurements Samples will be obtained from the radiolabeled fresh and stored
INTERCEPT Blood System for platelets before infusion and used as a radioactive standard. By
measuring the volume infused, the total dose of radioactivity infused will be calculated. In
vitro elution of the label from the transfused platelets will be determined by the BEST
elution assessment method, as well as the in vivo elution of radioactivity from the serial
blood samples obtained post-infusion of the labeled platelets.

The standard as well as the subject's whole-blood samples will be corrected for elution and
also for the residual activity in the cellular fraction one day after the infusion. Data
points 24 hours post-infusion will be used to calculate in vivo recovery after all
radioactive corrections have been made. The radioactivity of the samples will be determined
by use of a gamma counter. A multiple-hit model will be used to estimate the survival of the
radioactively labeled platelets.

Inclusion Criteria:

- Normal health status (as determined by the Investigator review of medical history and
blood donor physical exam)

- Meet FDA, American Association of Blood Banks (AABB), and site guidelines for blood
donation or apheresis platelet donation

- Complete blood count (CBC) and serum chemistry values within established reference
ranges or within guidelines as above.

- Pre-donation platelet count of more than 150×10^9 platelets/L

- Negative blood donor screening test panel for Human Immunodeficiency virus (HIV),
Hepatitis B virus (HBV), Hepatitis C virus (HCV), Human T-Lymphotropic virus (HTLV),
syphilis, and West Nile virus (WNV)

- Male and female subjects of childbearing potential must agree to use a medically
acceptable method of contraception throughout the study. A barrier method of
contraception must be included, regardless of other methods.

- Signed and dated informed consent form

Exclusion Criteria:

- Clinically significant acute or chronic disease (as determined by the Investigator)

- Pregnant or nursing females

- Male or female subjects of childbearing potential not using effective contraception

- Disease states or conditions that preclude blood donation or apheresis platelet
donation per AABB reference standards

- Treatment with aspirin or aspirin-containing medications within 7 days of apheresis or
treatment with non-steroidal anti inflammatory drugs (NSAID), anti-platelet agents or
other drugs affecting platelet viability within 3 days of apheresis (e.g. ibuprofen or
other NSAIDs)

- Subject received platelet inhibitor within 14 days of donation (e.g. clopidogrel,
ticlopidine)

- Splenectomized subjects

- History of known hypersensitivity to indium or chromium

- Participation in another clinical study currently or within the past 28 days