Screening


pivotal role in the success of an organisation’s drug discovery process, such that system failure (or lack of availability) has associated with it a cost. With this in mind HTStec recently undertook a survey to collect opinion on the reliability of automated HTS assay systems and the effect of reliability on output1. The objective was to try to understand the impact of reliability of HTS systems to the company’s research enterprise as a whole and to assign an economic value to the downtime of one of these HTS systems. Feedback was obtained from the supervisors, opera- tors, owners and the engineers that support HTS robotic assay systems. In this survey an ‘HTS sys- tem’ was defined as having robotically integrated capabilities for: 1) reagent/ liquid dispensing into assay plates; 2) assay plate incubation or holding; and 3) assay plate reading. Systems reviewed have a minimum on-board storage capacity of at least 150 assay plates and were able to process (screen) plates at a rate of at least 10,000 wells per 24h day. Assay workstations and other automated systems that pri- marily reformat compounds or create assay ready plates were excluded from the analysis. In the subsequent discussion we refer to an inte- grated HTS system as a ‘system’.


Typical system downtime


Survey respondents reported a mean system down- time (ie, not operating for any reason) of 8.1 days per month (Figure 1). In addition, 40% of respon- dents claimed their system was down for 10 days or more per month. This represents quite a signifi- cant under-utilisation of a resource that has associ- ated with it a large investment cost and a high operational cost. On average each system has a team of three FTE devoted to its operation. On closer investigation the majority (61%) of system downtime (ie, time the system was not being used for screening) was idle time, with scheduled repairs or maintenance accounting 14% of downtime and other (unclassified) downtime 6%. (Figure 2). The system downtime that was attributed to unsched- uled activities (ie, as a result of system breakdown or malfunction) was 19%. This equates to about 1.5 days per month when systems are down due to issues related to poor reliability.


System functioning at an acceptable level


Respondents reported that even when their systems were operational, only during 82% of this opera- tional time did their system function at an accept- able level (Figure 3). This means 18% of opera- tional time was at a level most respondents consid- ered unacceptable.


Drug Discovery World Winter 2010/11


Unscheduled activities (ie as a result of system breakdown or malfunction) 19%


© HTStec 2010


Idle time (ie nothing planned or scheduled) 61%


Figure 1: Average HTS system downtime (days/month)


25% Mean Downtime = 8.1 Days/Month 20% 15% 10% 9% 5% 0% None 1 2 3 4 5 6 7-9 © HTStec 2010 10-12 13-15 5% 5% 4% 4% 0% 0% 16-18 19-21 21-24 25-27 5% 4% 4% 2% 28-30 9% 16% 13% 21%


Figure 2: Breakdown of HTS system downtime


Other downtime 6%


Scheduled repairs or maintenance 14%


Figure 3: % Operational time HTS system functions at an acceptable level


10% 15% 20% 25% 30% 35%


0% 5%


34% Mean % Acceptable Operational Time = 82% 25%


14% 7% 5% 2% © HTStec 2010 0% 2% 2% 0% 0% 2% 0% 0% 0% 2% 0% 0% 0% 4% 2% 0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50% 55% 60% 65% 70% 75% 80% 85% 90% 95% 100%


63


% Responding


% Responding


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80