further information contact Sara Gibbons: Tel: +44 (0) 151 794 5553 Fax: +44
(0) 151 794 5656/5540 email: firstname.lastname@example.org
Drug Analysis Available
Protease Inhibitors - Saquinavir, Ritonavir, Indinavir, Nelfinavir, Amprenavir
NNRTIs - Delavirdine, Nevirapine, Efavirenz
Others - Sildenafil, Methadone, M8 (nelfinavir metabolite)
Samples - To aid us in the clinical interpretation of the results, it is helpful to have both a trough and a peak sample whenever possible. A trough sample should be taken as close to the end of the dosing interval as possible (i.e. at 12 h for bd regimens or 8 h for tds regimens). A peak sample should be taken approximately 1 h post dose for indinavir alone and 2 h post dose for indinavir with ritonavir and all other drugs. The dosing schedule for efavirenz makes it difficult to obtain trough and peak samples so we will try to give a clinical interpretation for samples from any known time point.
Blood samples should be collected in lithium-heparin tubes (or EDTA if heparinised tubes are unavailable) and plasma obtained by centrifugation within 2 h of collection. The minimum plasma sample volume required is 1 ml per drug analysed, e.g. if a single sample is analysed for saquinavir and ritonavir 2 ml of sample is required. Please do not overfill tubes and allow for expansion on freezing.
Sample Storage - If collection and transport of samples is to occur on the same day, the samples should be kept in a fridge at 4¡C prior to transport. If transport is to be later than 24 hours after collection plasma may be stored at -20¡C (or lower) and packed whilst frozen and allowed to thaw in transit.
Sample Details - Please complete the sample requisition form with as much information as possible to aid us in the interpretation of the results. Please ensure that samples are anonymised and the full name of the patient does not appear on the form or sample tube. The form is available as a Word 97 document or an Acrobat pdf file.
Transportation - Studies have shown that samples may remain at room temperature for 48 h with no effect on drug levels allowing overnight transportation without the need for packing on dry ice. Please notify us of your intention to send samples so we can ensure prompt handling on their arrival.
Samples may be sent First Class using the Royal Mail so long as all the requirements for the packing of pathological specimens are met. Please post early in the week (Monday-Wednesday) so packages do not remain in the University's mail room over the weekend. UN 602 packaging will be returned to the sender for reuse.
We are a member of the Hays DX system and samples may be sent using the PathPak service (Monday-Thursday). There is no charge to the sending laboratory as all inbound mail on this account is charged to us. This allows departments who are not members of an exchange to send samples from another department without incurring any cost to that department. Packaging will be returned to Hays for redistribution to exchanges.
Cost - The cost of analysis per sample is given below. When samples are analysed for saquinavir and nelfinavir under the scheme sponsored by HIV Focus (Roche Products Ltd), Roche will be invoiced directly for such samples.
Please note that when low dose ritonavir is given as a pharmacoenhancer (i.e. <400 mg), no clinical interpretation of the result will be provided and ritonavir will not be classed as PI for charging purposes. When given for antiretroviral activity (i.e.>/=400 mg), a clinical interpretation will be provided and ritonavir will be classed as a PI for charging purposes.
For full pharmacokinetic profiles or large numbers of samples, reduced costs may be available. Please contact Sara Gibbons or David Back to discuss rates.
Results - Samples will be analysed as soon as possible; we aim to send results out within two weeks of receiving the samples. When a fax number is given, results will be faxed and the original sent by second class post. In the absence of a fax number, results will be sent by first class post.
Delivery Address - See delivery address at bottom of the sample requisition form as a PDF file [27k].