12 
inquire about "stability" in human gene therapy than it would to ask about the 
lot stability of a kidney in a transplant operation. 
Dr. Vtelters asked if a patient might receive a second course of gene therapy. 
Dr. Anderson said it is conceivable a patient might require a second course of 
therapy. However, each course will be a de novo procedure, and lot consistency 
will not be relevant. 
Dr. Waiters said Dr. Miller's sixth comment was that the working group document 
should request a description of previously-reported similar human studies 
(including foreign studies) and their results. 
Dr. Walters said Dr. Miller had previously made this comment to the Working 
Group on Human Gene Therapy. Dr. Milewski pointed out that the working group 
at the April 1985 meeting had added language to Section I-B-3 in response to 
this comment. 
Dr. Walters said Dr. Miller's seventh suggestion is that Section I-B-2-c-(l)-(d) 
should be relocated to a position before Section I-B-2-c-(l) since Section 
I-B-2-c-(l )-(d) is relevant to gene therapy whether or not a retroviral system 
is used. 
Dr. Anderson said Section I-B-2-c-( 1 )-(c) is appropriately placed in the document 
since Section I-B-2-c-(l )-(c) specifically refers to the inherent properties 
of retroviral, vectors. He said the key question is whether the vector has 
sequences homologous with human sequences. Drs. Varmus and Temin specifically 
placed Section I-B-2-c-( 1 )-(d) in its current position in the document. 
The sukworkinq group agreed the language was appropriately placed in Section 
I-B-2-c- ( 1 ) - ( d ) . 
Dr. Anderson said the working group could consider adding parallel language 
to Section I-B-2-c-(3) ; this section deals with other host-vector systems. He 
could not envisage, however, that this addition would be useful since it would 
address pathogenicity. He did not think plasmid vectors would possess pathogenic 
qualities. 
Dr. Gottesman said while retroviruses have a mechanism to express pathogenicity, 
there is no evidence to suggest plasmid vectors might possess pathogenicity 
mechanisms. It is, thus, not logical to pose a question in Section I-B-2-c-(3) 
referring to plasmid pathogenicity. If a potential pathogenicity mechanism 
cannot be envisaged for plasmid vectors, hew could the vector be designed to 
avoid the consequences of pathogenicity? She said the current points to 
consider document is inclusive and adequately addresses the pertinent issues. 
The suhworking group agreed. 
Dr. Walters said Mr. Miller's eighth suggestion is that the phrase "specifically 
germ line cells" should be deleted frem Section I-B-2-c-( 2 ) because apprehension 
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