PT  - JOURNAL ARTICLE
AU  - Shahriar S. Yaghoubi
AU  - Marcelo A. Couto
AU  - Chang-Cheng Chen
AU  - Lathasree Polavaram
AU  - Guanggen Cui
AU  - Luyi Sen
AU  - Sanjiv S. Gambhir
TI  - Preclinical Safety Evaluation of <sup>18</sup>F-FHBG: A PET Reporter Probe for Imaging Herpes Simplex Virus Type 1 Thymidine Kinase (HSV1-tk) or Mutant HSV1-sr39tk's Expression
DP  - 2006 Apr 01
TA  - Journal of Nuclear Medicine
PG  - 706--715
VI  - 47
IP  - 4
4099  - http://jnm.snmjournals.org/content/47/4/706.short
4100  - http://jnm.snmjournals.org/content/47/4/706.full
SO  - J Nucl Med2006 Apr 01; 47
AB  - 9-(4-18F-Fluoro-3-[hydroxymethyl]butyl)guanine (18F-FHBG) is a sensitive and specific PET reporter probe for imaging the PET reporter genes, herpes himplex 1 thymidine kinase (HSV1-tk) and its mutant HSV1-sr39tk. 18F-FHBG has suitable pharmacokinetics and dosimetry for clinical applications and imaging of HSV1-TK has been demonstrated in the livers of hepatocellular cancer patients. Methods: Male and female Sprague–Dawley rats and New Zealand White rabbits were divided into equal groups receiving either 14 μg/kg cold FHBG or carrier solution, for a 14-d acute toxicity assessment. We monitored body weight, food and water consumption, body temperature, cardiovascular electrical and functional indices, respiratory performance and oxygen saturation, comprehensive blood chemistry, complete blood count (CBC), and urinalysis. We conducted daily cage-side examinations for the detection of any clinical abnormalities. Tissues of the animals that were euthanized and necropsied on day 14 were prepared for histopathologic examination. Results: No significant differences in cardiovascular and respiratory parameters, food consumption, body weight, urine components, or clinical signs attributable to test article toxicity were observed between the treatment and control groups. Any differences noted in the blood chemistry and CBC parameters were deemed to be incidental findings unrelated to the administration of the FHBG. Conclusion: Acute toxicity evaluation of FHBG at 100 times the expected human dose does not indicate harm to organ function or tissues. The Food and Drug Administration has approved FHBG as an Investigational New Drug.