Abstracts

Durable Clearance Of Genital Warts Following Hspe7 Immunization

Abstract presented at HPV 2002 - Paris, France

Goldstone, S. (1), Fife, K. (2), Fine P (3), Hagensee, M. (4), Palefsky, J. (5), Neefe, J. (6)

1) Mt. Sinai School of Medicine, NY, USA
2) Indiana Univ., Indianapolis, USA
3) Baylor, Houston, USA
4) LSUHSC, New Orleans, USA
5) UCSF, San Francisco, USA
6)Stressgen Biotechnologies, Inc., San Diego, CA, USA

Background:
We tested a novel HPV-specific immunotherapy composed of heat shock protein Hsp65 from BCG fused to HPV16 E7.

Methods:
HspE7, 500 mcg monthly x 3, was given in an open label trial (9902) to patients (pt) with high grade anal dysplasia. Warts were not a study parameter, but one site (SG) reviewed records of 27 pt with concomitant anorectal warts to assess wart response for up to 24 months (m) from first injection. Complete response (CR) was absence of warts by examination. Trial 0004 randomized 54 warts pt to HspE7 (in the same regimen) or placebo (P). CR status at 6 m was assessed.

Results:
In trial 9902, which is ongoing, 23, 17 & 11 pt were evaluable at 12, 18 & 24 m. The CR rate for warts was 48, 65 & 73%. Most CR were first seen by 12 m. CR was durable: no pt ever in CR had a recurrence of warts and 75% of CR seen at 24 m had persisted at least 12 m. In 0004, CR at 6 m was 36% for HspE7 and 25% for P. Like CR in 9902, more CR might have been seen after 6 m. As reported with imiquimod, warts in women responded well and penile warts responded poorly. In women, the CR rate at 6 m was 62% (HspE7) and 20% (P) and most CR occurred by 3 m. For men with only anal/perianal warts the CR rate at 6 m was 42% (HspE7) and 25% (P). Men with penile warts responded much less well. Most pt in both studies carried HPV 6 or 11 by anal swab or wart biopsy and few carried HPV 16.

Conclusions:
HspE7 results in a high proportion of durable CR within 12 m of initial treatment. Men with anal/perianal warts and women respond better than men with penile warts. CR of warts suggests this HPV16 vaccine induces cross-reactive immunity.