Journal ofNeuro-Oncology 62: 145-156, 2003.
`© 2003 Kluwer Academic Publishers. Printed in the Netherlands.
`
`Tissue uptake of BSH in patients with glioblastoma in
`the EORTC 11961 phase I BNCT trial
`
`, Frank Grochulla4
`, Philippe Paquis3
`, Claudia Gotz2
`, Andrea Wittig 1
`, Wolfgang Sauerwein 1
`Katalin Hideghety 1
`, Ray Moss7
`, Martin de Vries 10 and
`Klaus Haselsberger5
`, John Wolbers6
`, Rene Huiskamp8
`, Heinz Fankhauser9
`Detlef Gabel 11
`1 Department of Radiotherapy, University Essen, Germany; 2 Department of Neurosurgery, Klinikum Groj3hadern,
`Munich, Germany; 3 Department of Neurosurgery, Hopital Pasteur CHU, Nice, France; 4Department of
`Neurosurgery, Zentralkrankenhaus Bremen, Germany; 5 Department of Neurosurgery, Karl-Franzens-University,
`Graz, Austria; 6 Department of Neurosurgery, Vrije Universiteit Amsterdam, The Netherlands; 7 Institute for
`Energy, Joint Research Centre, European Commission, 8 Nuclear Research and Consultancy Group NRG, Petten,
`The Netherlands; 9 Department of Neurosurgery, CHUV, Lausanne, Switzerland; 10 NDDO Oncology, Amsterdam,
`The Netherlands; 11 Department of Chemistry, University Bremen, Germany
`
`,
`
`Key words: BNCT, glioblastoma, ESH tissue uptake, ESH toxicity
`
`Summary
`
`Purpose: The uptake of the boron compound Na2B 12H 10-SH (ESH) in tumor and normal tissues was investigated in
`the frame of the EORTC phase I trial 'Postoperative treatment of glioblastoma with BNCT at the Petten Irradiation
`Facility' (protocol l 1961).
`Methods and Materials: The boron concentration in blood, tumor, normal brain, dura, muscle, skin and bone was
`detected using inductively coupled plasma-atomic emission spectroscopy in l 3 evaluable patients. In a first group
`of I 0 patients I 00 mg BSH/kg bodyweight (BW) were administered; a second group of 3 patients received 22.9 mg
`BSH/kg BW. The toxicity due to BSH was evaluated.
`Results: The average boron concentration in the tumor was 19.9 ± 9.1 ppm ( l standard deviation (SD)) in the
`high dose group and 9.8 ± 3.3 ppm in the low dose group, the tumor/blood ratios were 0.6 ± 0.2 and 0.9 ± 0.2,
`respectively. The highest boron uptake has been detected in the dura, very low uptake was found in the bone, the
`cerebro-spinal fluid and especially in the brain (brain/blood ratio 0.2±0.02 and 0.4±0.2). No toxicity was detected
`except flush-like symptoms in 2 cases during a BSH infusion at a much higher speed than prescribed.
`Conclusion: BSH proved to be safe for clinical application at a dose of 100 mg ESH/kg infused and at a dose
`rate of 1 mg/kg/min. The study underlines the importance of a further investigation of BSH uptake in order to
`obtain enough data for significant statistical analysis. The boron concentration in blood seems to be a quite reliable
`parameter to predict the boron concentration in other tissues.
`
`Introduction
`
`Boron neutron capture therapy (BNCT) is a radio(cid:173)
`therapy modality based on the nuclear reaction that
`occurs when the non-radioactive isotope boron-10
`captures a thermal neutron. The released high LET
`radiation consists of an alpha particle and a Li-nucleus
`with a range in tissue of approximately lO µm. The
`
`effects of this irradiation with high biological effec(cid:173)
`tiveness are therefore limited to approximately one
`cell diameter. In principle, one event liberates enough
`energy to kill one cell. However, neutron capture ther(cid:173)
`apy is clinically attractive only if a sufficiently high
`thermal neutron ftuence can be delivered to the tar(cid:173)
`get volume and if a sufficiently high concentration
`of 10B can be obtained in the tumor, with relatively
`
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`

`

`146
`
`low concentrations in the surrounding healthy tissue.
`Knowledge about tissue uptake of boron compounds
`available for BNCT is therefore of major importance.
`Up to now, only two agents are available for clini(cid:173)
`cal investigation: the boron cluster sodium mercapto(cid:173)
`10B 12H10SH, referred to
`undecahydrododecaborate Na2
`as BSH [1,2] and the amino acid analogue para(cid:173)
`10BN04 (BPA) [3,4].
`boronophenylalanine C9H12
`Both compounds are being used in actual clinical
`trials for glioblastoma and melanomas [5,6]. BSH was
`first used in 1968 by Hatanaka and more recently by
`Nakagawa [7,8] in Japan to treat malignant glioma in
`individual patients. It was also used in several studies to
`evaluate its pharmacokinetic properties and the biodis(cid:173)
`tribution of 10B as delivered by BSH. BSH is also under
`evaluation in the EORTC phase I trial 11961 'Postop(cid:173)
`erative Treatment of Glioblastoma with BNCT at the
`Petten Irradiation Facility' (EORTC: European Organ(cid:173)
`isation for the Research and Treatment of Cancer)
`[9, 10]. As part of this clinical trial an investigation of
`the uptake of BSH in the tumor and in surrounding
`tissues has been performed. The results of this research
`are presented in this paper.
`
`Methods and patients
`
`The clinical trial
`
`The phase I protocol EORTC 11961 is a dose find(cid:173)
`ing trial. Its primary aim is to determine systemic and
`local toxicity of boron neutron capture therapy (BNCT)
`with the compound BSH, after craniotomy with gross
`total tumor resection in patients with glioblastoma
`multiforme. It investigates the qualitative and quanti(cid:173)
`tative dose-limiting toxicity and maximum tolerated
`dose of this regimen and aims to establish the max(cid:173)
`imum tolerated radiation dose of BNCT to healthy
`tissues under well-defined conditions of cranial irradi(cid:173)
`ation. Cohorts of patients are irradiated in 4 fractions
`at the same radiation dose level with epithermal neu(cid:173)
`trons at the European Commission's research reactor
`High Flux Reactor (HFR) in Petten (NL). The aver(cid:173)
`age 10B-concentration in blood over the 4 fractions is
`30 ppm for all patients. The increase of radiation dose
`from one cohort to the next is obtained by increas(cid:173)
`ing the irradiation time. Systemic toxicity due to the
`drug is investigated up to 30 days after BSH infusion
`and is reported using the Common Toxicity Criteria
`of the National Cancer Institute (NCI CTC). For the
`grading of adverse events during the first 90 days after
`
`radiotherapy, NCI CTC and EORTC/RTOG (RTOG:
`Radiation Therapy Oncology Group) early radiation
`toxicity criteria are applied. After this observation
`period, EORTC/RTOG late radiation morbidity scales
`are used in combination with SOMA [9].
`The secondary goal of the study is to evaluate the
`10B-uptake in tumor and healthy tissues. Therefore,
`protocol 11961 includes a tissue uptake study for the
`first cohort of patients included in the trial.
`The multi-center study includes 5 participating
`patient referral centers from 4 different countries:
`the Departments of Neurosurgery at the Klinikum
`GroBhadern in Munich (D), the CHU Hopital Pasteur,
`Nice (F), the Zentralkrankenhaus Bremen (D), the
`Karl-Franzens-University, Graz (A) and the Vrije Uni(cid:173)
`versiteit Amsterdam (NL). The study center is the
`Department of Radiotherapy of the University Essen
`(D). In order to assure the quality of the work to be per(cid:173)
`formed, it is necessary to create a very specialized orga(cid:173)
`nization and contractual structure [ 14 J. Furthermore,
`due to the fact that a new drug, a new radiation beam
`and a new facility are used, special efforts were made
`on quality management. A detailed description of all
`procedures is provided in written form (Standard Oper(cid:173)
`ating Procedures, SOP's) to all participating institutes.
`The infrastructure and preparation are controlled and
`the study procedures are agreed and practiced in detail
`during an initiation site visit. In addition to the case
`report forms, special study documents are provided
`(source document forms, submission forms) to achieve
`a high degree of unambiguity and uniformity [9].
`
`Tissue sampling
`
`In the first cohort of patients, the tissue uptake of boron
`after infusion ofBSH was investigated. Prior to surgery,
`BSH was administered at the same amount as foreseen
`for the first fraction of irradiation: 100 mg/per kg BW.
`The time interval between infusion and operation was
`the same as that intended for BNCT: 12-14 h. During
`surgery, tissues were collected from areas where expo(cid:173)
`sure to the neutron beam during the planned BNCT was
`expected. The sampling was performed in a way so as
`not to compromise the planned surgical intervention,
`which led to the collection of different numbers of spec(cid:173)
`imens in each individual patient. The following tissues
`were collected during surgery: tumor, non-tumor brain
`tissue, dura mater, calvarium, muscle, skin and cerebro(cid:173)
`spinal fluid (CSF). Whenever possible, samples were
`acquired from a number of different locations in the
`
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`
`

`

`tumor. Blood was collected at the same time as tissue
`sampling. The content of boron in blood and tissues was
`measured by inductively coupled plasma-atomic emis(cid:173)
`sion spectroscopy (ICP-AES) at the Nuclear Research
`and consultancy Group (NRG) Petten [12,13].
`
`Analytical procedure
`
`For the ICP-AES, the 249.773 nm emission line was
`chosen to measure boron. For a 4 ml sample, the detec(cid:173)
`tion limit, defined as the mean value of the back(cid:173)
`ground +3 SDs, was between 0.001 and 0.015 ppm.
`This allowed the detection of between 0.04 and 0.6 ppm
`of boron in tissue sample with the size of I g. All mea(cid:173)
`surements were done in triplicate with a coefficient of
`variation of less than 2%. Internal standard samples
`were measured with prompt gamma ray spectroscopy.
`
`Boron compound
`
`Boron-10 enriched (>95%) BSH is prepared as a
`chemically defined compound supplied in vials, each
`containing I 000 mg of the substance. Supplying com(cid:173)
`panies have to produce the compound according to a
`drug master file, in which a written procedure has to be
`followed for preparation and quality control of the final
`product and its intermediates. The material is imported
`into The Netherlands by the Pharmacy Department of
`the University/Academic Hospital 'Vrije Universiteit'
`(AZVU) in Amsterdam [15]. Prior to use in humans,
`strict quality checks are performed for each batch fol(cid:173)
`lowing standard operating procedures (SOP). In the
`laboratory of the AZVU pharmacy, the following qual(cid:173)
`ity control checks are performed:
`
`1. Identification of the study medication: Test for the
`presence of sodium and identification of the product
`by infrared absorption spectrophotometry.
`in
`its
`ionic form
`2. Tests on purity of BSH
`[(B 12H 10SHh]- as well as absence of its oxidation
`products [(B24H22SH2)i and (B24H22S20)4]-: This
`is tested by high-pressure liquid chromatography.
`The material is defined to meet the requirements if
`the total of the oxidation products is less than 2%.
`3. Absence of bacterial endotoxins (pyrogens): This
`is tested by Limulus Amoebocyte Lysate test. The
`material is defined to meet the requirements if it
`contains less than 0.025 IE pyrogens/mg BSH.
`4. Assays of the study medication: These tests are
`carried out at NRG in Petten using ICP-AES and
`
`147
`
`prompt gamma spectroscopy under the auspices
`of the AZVU pharmacists according to written
`procedures:
`• BSH content: The material is defined to meet the
`requirements if the total amount of BSH in each
`tested vial is 95-105% of the stated value.
`• Degree of enrichment: The material is defined to
`meet the requirements if the degree of enrichment
`is >95%.
`
`The responsibility for the quality control and for the
`release of the material for clinical use is delegated to
`two independent pharmacists. If the batch meets all
`requirements, the pharmacist releases it for clinical
`use with an expiry date one year after initial testing.
`After labeling conforming to good clinical practice,
`the material is sent to the collaborating centers together
`with a certificate of analysis provided by the Pharmacy
`Department of the AZVU and a declaration that the
`material is suitable for clinical use. Before administra(cid:173)
`tion to the patient, the drug is dissolved under aseptic
`conditions. A vial containing lg BSH is dissolved in
`!Om! distilled water. This solution is sterile-filtered
`using a 0.2 µ,m sterile filter and added to a 0.9% NaCl
`infusion to obtain a total volume of 500 ml to contain
`I 00 mg BSH/kg BW of a given patient. It is always
`required to use the total amount of one vial containing
`I g BSH. Rounding should be to lower values (e.g. for
`a patient weighing 75 kg, seven vials of I g each are
`used). The material remains stable at room temper(cid:173)
`ature for at least 6 h and is administered within that
`time interval. The infusion rate is defined to be I mg
`BSH/kg BW/minute. If feasible, the infusion should
`be given through a central venous catheter.
`
`The patients
`
`Fourteen patients (12 males and 2 females), in the
`age range between 51 and 74 years (mean: 61.2
`years), weighing between 56 and 109 kg with operable
`glioblastoma multiforme (GBM) as suspected by CT
`and MRI images were admitted to the first cohort of
`the study after informed consent was given (Table 1 ).
`Central pathology review at the German Brain Tumour
`Reference Centre in Bonn (Prof. Wiestler, Bonn,
`Germany) revealed GBM (WHO grade IV) in 11
`patients and Gliosarcoma (WHO grade IV) in 3 patients
`from tumor samples received from the respective neu(cid:173)
`rosurgeon. Of these, 13 patients could be evaluated
`from the point of view of tissue boron uptake. None of
`the patients had reduced kidney or liver function, and
`
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`

`

`148
`
`Table 1. Demographic data of treated patients and BSH dose
`
`Patient Gender Age Performance status Dose ofBSH
`(Karnofsky)
`(mg/kg)
`
`101
`102
`103
`104
`105
`106
`107
`108
`109
`110
`111
`112
`113
`114
`
`M
`M
`M
`M
`M
`F
`F
`M
`M
`M
`M
`M
`M
`M
`
`74
`52
`73
`59
`56
`63
`57
`71
`60
`58
`64
`51
`51
`68
`
`80
`80
`90
`70
`80
`90
`90
`100
`80
`100
`JOO
`90
`100
`100
`
`103.9
`101.4
`100.0
`98.2
`90.9
`95.2
`89.7
`92.l
`94.6
`89.9
`20.4
`21.l
`8.8
`27.3
`
`none suffered from any other malignant disease. The
`first I 0 patients were infused 14 h prior to surgery with
`lOOmg BSH/kg BW (range 89.7-103.9), at an infu(cid:173)
`sion rate of 1 mg BSH/kg BW/min according to the
`protocol plan. The total amount of BSH infused varied
`between 5000 and 9000 mg. Due to a temporary lack
`of an adequate amount of BSH, three patients received
`only a total dose of 2000 mg BSH each, corresponding
`to 20.4-28.2 mg BSH/kg BW (22.9 mg BSH/kg BW on
`average) infused at the same rate. One patient (#113)
`received only 8.8 mg BSH/kg BW and was excluded
`from this evaluation.
`For the patients who received 100 mg BSH/kg BW,
`the boron concentration in tissues was evaluated nor(cid:173)
`malized to I 00 mg BSH/kg BW, assuming that the
`amount of boron in the tumor and in other tissues
`increases proportionally with the dose of BSH admin(cid:173)
`istered [16,17]. For the 3 patients who received only a
`total dose of2 g BSH, the boron concentration was eval(cid:173)
`uated normalized to 22.9 mg BSH/kg BW, being the
`average dose of BSH given to these 3 patients (range:
`20.4-27.3 mg BSH/kg BW).
`
`Results
`
`The boron contents in all tumor and tissue specimens of
`the individual patients are presented in Tables 2 and 3.
`Due to the limited number of samples available, a SD
`cannot be calculated for all values.
`
`Tumor
`
`The maximum number of tumor samples taken from
`any patient was 5, for 5 patients only one sample
`
`from the operated tumor was made available. In some
`patients only one sample could be taken in order not
`to compromise the surgical procedure. A total average
`value over all samples has been evaluated. The aver(cid:173)
`age boron-concentration in tumor was 19.8 ± 9.3 ppm
`(lSD) for the patients who received 100 mg BSH/kg
`BW and 9.8 ± 3.3 ppm for the 3 patients who received
`only 22.9 mg BSH/kg BW. The boron content in tumor
`tissue varies considerably from one patient to another.
`In the cases in which several samples from one single
`tumor were available, a highly heterogeneous boron
`distribution was observed in the individual tumor sam(cid:173)
`ples. The average tumor to blood ratio at the time point
`of the tissue sampling ( 12 h after the BSH infusion) was
`0.6 and 0.9, respectively, in the 2 groups of patients.
`The average tumor to blood ratio was with the excep(cid:173)
`tion of one patient always less than 1. It is also just
`as significant to note that there was considerable intra(cid:173)
`tumoral variability in boron uptake.
`
`Brain
`
`The 'brain' tissue investigated was tissue adjacent to
`the tumor, which had to be removed in order to oper(cid:173)
`ate the tumor. No brain tissue at a distance from the
`tumor site was taken. The average boron concentration
`in the brain tissue adjacent to the tumor was 6.6 ppm
`in the patients who received 100 mg BSH/kg BW and
`3.5 ppm in patients who received 22.9 mg ESH/kg BW.
`In all patients, the average boron concentration in brain
`was lower than in blood, tumor and all other tissues
`investigated, only in bone the boron concentration was
`even lower than in brain. The tumor to brain ratio for
`the two groups of patients was 2.9 and 3.0, respectively,
`the brain to blood ratio was 0.2 and 0.4.
`
`Additional normal tissues
`
`There was a clear difference in boron content between
`the different tissues investigated. The boron concentra(cid:173)
`tion in the cranial bone was always very low: 5.3 ±
`2.7ppm. The bone to blood ratio was 0.2 ± 0.1in3
`patients who received the high dose of BSH and 0.1
`in the patient who received the lower dose.
`Very high boron uptake was detected in skin with an
`average boron concentration of 42.1 and 11.8 ppm in
`the second dose group and dura (51.2 and 21.1 ppm).
`The SD was also very high. In muscle tissue a lower
`boron uptake was detected (24.3 and 7.8 ppm).
`Cerebra-spinal fluid was collected for boron analy(cid:173)
`sis from 2 patients only: one sample had to be excluded
`
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`
`

`

`Table 2. Boron concentration measurements in normal tissue and tumor specimens. The table indicates the absolute BSH dose that was applied to the
`individual patients. The boron measurements in all tissues and blood were normalized to 100 mg/kg BW
`
`Patient no.
`
`101
`
`102
`
`103
`
`104
`
`105
`
`106
`
`107
`
`108
`
`109
`
`110
`
`Average
`101-110
`
`Standard
`deviation( s)
`
`103.9
`0.96
`
`101.4
`0.99
`
`100.0
`1.00
`
`98.2
`1.02
`
`mg BSH/kg
`Normalization factor
`to 100 mg BSH/kg
`BW
`Boron concentration in normal tissues and in tumor (ppm)
`28.7
`35.5
`48.9
`33.7
`30.6*
`
`Blood
`CSF
`Skin
`Muscle
`Bone
`Dura
`Brain
`Tumor
`Tumor
`Tumor
`Tumor
`Tumor
`Tumor (average)
`SD
`
`21.6
`11.l
`
`38.2
`
`17.8
`
`35.2
`8.6
`42.2
`
`16.5
`18.2
`25.4
`21.1
`21.6
`20.6
`3.4
`
`15.0
`3.7
`17.8
`
`20.6
`18.8
`13. l
`
`17.5
`3.9
`
`9.4
`27.3
`41.8
`23.9
`
`31.0
`9.5
`
`90.9
`I.JO
`
`95.2
`1.05
`
`89.7
`1.11
`
`92.l
`1.09
`
`94.6
`1.06
`
`89.9
`1.11
`
`95.6
`1.05
`
`5.1
`0.05
`
`43.0
`
`27.5
`
`29.6
`
`15.2
`
`15.1
`
`30.7
`
`16.2
`
`38.9
`24.2
`
`7.5
`11.7
`
`137.0
`62.8
`6.4
`145.8
`4.7
`12.5
`3.0
`
`25.l
`2.3
`19.5
`12.8
`
`104.1
`4.1
`21.5
`
`26.5
`
`42.9
`
`34.2
`
`42.1
`24.3
`5.3
`51.2
`6.6
`
`44.7
`21.5
`2.6
`34.2
`8.2
`12.8
`
`14.5
`20.5
`
`31.4
`
`12.7
`26.2
`
`8.2
`
`47.8
`17.3
`2.7
`43.9
`2.6
`
`31.6
`
`9.6
`
`7.7
`
`19.5
`
`12.8
`
`19.9
`
`9.1
`
`Ratios of boron between different tissues
`0.5
`0.6
`Tumor/blood
`3.3
`Tumor/brain
`Skin/blood
`Bone/blood
`Dura/blood
`Brain/blood
`
`0.6
`
`1.1
`
`0.2
`
`0.6
`
`0.6
`
`0.7
`
`0.2
`
`0.1
`0.6
`
`0.7
`
`0.3
`
`0.6
`
`0.6
`
`0.3
`1.7
`4.6
`0.2
`4.9
`0.2
`
`0.9
`5.2
`0.8
`
`4.2
`0.2
`
`0.7
`
`0.5
`
`1.2
`
`0.3
`1.6
`1.0
`0.1
`0.8
`0.2
`
`0.6
`2.9
`1.4
`0.2
`1.8
`0.2
`
`0.2
`1.7
`1.6
`0.1
`1.7
`0.02
`
`'Value not representative. Sample was contaminated with blood.
`
`......
`""" '°
`
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`
`

`

`150
`
`Table 3. Boron concentration measurements in normal tissue and was detected in this tissue uptake study after a single
`tumor specimens. The table indicates the absolute BSH dose that was dose of BSH.
`applied to the individual patients. The boron measurements in all
`tissues and blood were normalized to 22.9 mg/kg BW
`
`Patient no.
`
`111
`
`112
`
`114
`
`Average
`111-114
`
`Standard
`deviation(s)
`
`20.4
`1.12
`
`21.l
`1.09
`
`27.3
`0.84
`
`22.9
`1.02
`
`3.8
`0.15
`
`mgBSH/kg
`Normalization
`factor to
`22.92mg
`BSH/kgBW
`
`Discussion
`
`The aim of this part of the study protocol EORTC
`11961 was to collect tissue uptake data under circum(cid:173)
`stances that simulate those that would be carried out
`clinically for BNCT. Therefore, the BSH was admin(cid:173)
`istered prior to surgery in the therapeutic dose range
`( 100 mg/kg BW) and the time point of the surgery (i.e.
`the time point of the tissue sampling) was defined to
`be the same as the planned time point of the irradiation
`at the HFR Petten [5,9). The intention of these specific
`conditions was to obtain enough data on pharmacoki(cid:173)
`netics to be able to adjust during the week of irradiation
`the boron concentration in blood to achieve an average
`boron concentration of 30 ppm in blood over 4 frac(cid:173)
`tions and to obtain reliable data on boron concentration
`in tissues for further evaluation of the absorbed dose.
`From the data collected and analysed, it was learnt that
`the data obtained during surgery, was not a prerequi(cid:173)
`site that BNCT at the HFR Petten could be performed
`in a correct way. The heterogeneity in the values of
`boron uptake in tissues could form no basis to calcu(cid:173)
`late the absorbed radiation dose for individual patients.
`Other important points that should be noted were the
`extremely time (and money) consuming quality man(cid:173)
`agement procedures, which at the moment of closing
`the first cohort, were judged to be too extensive for col(cid:173)
`lection of data, which would not be needed to reach the
`main goal of the trial. Therefore, the tissue uptake com(cid:173)
`ponent of the EORTC protocol 11961 was abandoned
`after closure of the first cohort. ln particular, the high
`degree of complexity required to organize and coordi(cid:173)
`nate such a collection of tissues in a reliable way for a
`multicenter trial, cannot be stressed enough. The small
`number of patients, included in the phase I trial, made
`it difficult to establish a regular routine, which should
`be seen as a prerequisite for reliability and efficacy.
`The extremely sensitive analytical methods may be
`influenced by several parameters, some of which are
`difficult to control in the real clinical situation. For
`example, incorrect handling of the samples in the
`operating theater may be a major source of artifacts.
`Prior to weighing and freezing, a tissue sample placed
`aside for several minutes under the glare of the theater
`spotlights, may lead to some evaporation of water and
`therefore to misleadingly high boron concentrations
`
`Boron concentration in normal tissues and in tumor (ppm)
`11.5
`Blood
`14.8
`6.4
`10.9
`4.2
`21.0
`7.0
`8.0
`Skin
`7.3
`11.8
`Muscle
`12.2
`3.3
`7.8
`Bone
`1.5
`36.4
`Dura
`21.1
`5.8
`Brain
`3.5
`13.9
`Tumor
`10.8
`Tumor
`Tumor (average) 12.4
`
`2.1
`
`9.8
`
`3.3
`
`1.5
`
`1.6
`7.7
`
`5.8
`3.3
`6.6
`
`Ratios of boron between different tissues
`Tumor/blood
`0.8
`0.7
`1.0
`2.2
`4.9
`Tumor/brain
`2.0
`I. I
`Skin/blood
`0.6
`1.4
`0.1
`Bone/blood
`Dura/blood
`Brain/blood
`
`2.5
`0.4
`
`0.1
`
`0.9
`0.5
`
`0.9
`3.0
`I. I
`0.1
`1.7
`0.4
`
`0.2
`1.6
`0.4
`
`0.2
`
`from further evaluation because of blood contamina(cid:173)
`tion (the boron concentration value was 30.6 ppm). The
`measured boron concentration in the second sample
`was 2.1 ppm.
`
`Side effects during and after ESH infusion
`
`A transient 'flush' reaction characterized by redness
`of the head and neck and warm sensation with(cid:173)
`out increase of body temperature was observed in
`the two patients who had received the BSH infu(cid:173)
`sion at a rate higher than 1 mg/kg/min during a short
`period. One of the patients with a medical back(cid:173)
`ground, changed the rate of infusion herself in order
`to finish it more quickly. The second patient, in
`contrast to the protocol, was infused at the start with
`500 ml/h instead of 300 ml/h. The symptoms disap(cid:173)
`peared when the speed of the BSH infusion was
`decreased. All the other 12 patients were completely
`free of these reactions. No other BSH related toxicity
`
`CFAD v. Anacor, IPR2015-01776, CFAD EXHIBIT 1072 - Page 6 of 12
`
`

`

`in the analysis (which may explain the data obtained
`in patient 107). Incorrect handling of the weighting(cid:173)
`balance in the operating theatre will also lead to wrong
`results. Packages, containing samples sent from differ(cid:173)
`ent hospitals to the analysing institute may be easily
`lost, especially if arriving during the weekend. Further(cid:173)
`more, the boron analysis itself has numerous pitfalls. In
`conclusion, to obtain reliable data demands a tremen(cid:173)
`dous effort in quality management and control that is
`difficult to maintain in a multicenter trial without suf(cid:173)
`ficient financial resources. Nevertheless, for the first
`cohort, which included a total of 14 patients, substan(cid:173)
`tial efforts had to be, and were, made and consequently,
`data is available.
`Despite the clinical application ofBSH for BNCT by
`Hatanaka since 1968[7,18] detailed biodistribution and
`pharmacokinetic data for BSH only recently became
`available [ 17, 19-25]. Some of these investigations
`were performed to prepare a European BNCT trial,
`which was finally realized through EORTC 11961.
`Despite the common goal, the EORTC and Japanese tri(cid:173)
`als were designed and performed independent of each
`other. The amount of BSH administered to the patients
`was, in most cases, very low ( <30 mg BSH/kg BW).
`Stragliotto and Fankhauser [ 17 J reported tumor uptake
`data for BSH in a group of 61 patients for a variety of
`brain tumors. Haritz et al. [20] published the data of 24
`patients with high-grade gliomas. Haselsberger et al.
`[ 19], who reported a series of l 0 patients with histolog(cid:173)
`ically confirmed GBM, obtained the most homogenous
`data set. Gabel et al. [ 16] summarized several of these
`European biodistribution studies. Table 4 summarizes
`all these investigations.
`As well as, and independent of the efforts coordi(cid:173)
`nated through EU grants, three other important analy(cid:173)
`ses have been published in the past years.
`Kageji et al. [25] reported on the pharmacokinetics
`and uptake of BSH in a series of 123 patients treated
`by Hatanaka between 1968 and 1994. At the begin(cid:173)
`ning of this series, the BSH was administered intra(cid:173)
`arterially and later intravenously. In Japan, BNCT has
`always been performed as an intraoperative irradiation;
`therefore, it was possible to analyze tissues removed
`during the surgery, immediately prior to irradiation.
`However, a controlled prospective clinical trial was
`never designed and performed, therefore, only the
`retrospective description of the carefully collected data
`is available. Its interpretation is therefore limited not
`only due to the changes in the clinical procedures but
`also in the analytical methods.
`
`151
`
`Horn et al. [23] performed a pharmacokinetic and
`tissue biodistribution study of BSH, administered i.v.
`at a dose of 25 mg BSH/kg BW in 1 h, in a group of
`10 patients suffering from high-grade glioma. Tumor
`boron values were measured at 4 different time points
`after infusion leading to a very small number of patients
`per time point.
`Goodman et al. [24) performed a biodistribution
`and pharmacokinetic study, which under strictly con(cid:173)
`trolled conditions, focused especially on the issue of
`variability in tumor boron uptake. Of the 25 patients
`entered in the study, only 19 were finally diagnosed
`and could be confirmed to have malignant glioma
`WHO III or IV and thus eligible for evaluation.
`Different amounts of BSH were administered (26.5,
`44.1 and 88.2 mg/kg BW), which also resulted in a
`small number of values available for one observation
`point.
`Due to the low dose of BSH administered in the
`majority of the patients, the variations in the time inter(cid:173)
`vals between administration and tissue sampling, the
`logistic problems already mentioned and the different
`techniques used for boron analysis, it is difficult to draw
`firm conclusions regarding the BSH uptake in tumor
`and normal tissues from the studies reported.
`
`Time point of tissue sampling
`
`An important parameter, which may influence the out(cid:173)
`come after BNCT, is the time interval between the
`application of the drug and the irradiation. Despite the
`fact, that it is very difficult to draw clear-cut recommen(cid:173)
`dations from the numerous publications, all authors
`who use BSH for BNCT apply it 12-14 h before irra(cid:173)
`diation. This procedure is based especially on the con(cid:173)
`siderable Japanese experience [26] but is also sup(cid:173)
`ported by the results of Horn et al. [23), Stragliotto
`and Fankhauser [17), as well as Gabel et al. [16].
`Kageji et al. [25] suggest even a longer time inter(cid:173)
`val of 15-20h between infusion of BSH and irradi(cid:173)
`ation, which is not feasible if BNCT is applied in
`several daily fractions. Goodman et al. [24] investi(cid:173)
`gated the tissue uptake 3-7 h after infusion, as well
`as an additional group of 3 patients with anaplastic
`astrocytoma, from whom tissue samples were obtained
`after 12 h. No values of boron concentration in blood
`at the time point of tissue sampling were reported.
`The data obtained in the EORTC trial, presented
`here, cannot contribute to this discussion, as the time
`
`CFAD v. Anacor, IPR2015-01776, CFAD EXHIBIT 1072 - Page 7 of 12
`
`

`

`152
`
`Table 4. Overview of previous studies of JOB tissue uptake and pharmacokinetics after ESH-administration. Values cannot be directly
`compared because of considerable differences in (1) the amount ofBSH infused, (2) the time interval between ESH-infusion and tissue
`sampling, (3) route of BSH administration (4) differences in values given by the authors e.g. mean, median, SD or range of values
`
`Amount of
`BSH(mg
`BSH/kg BW)
`(range)
`
`Infusion time Time interval
`between
`infusion and
`tissue
`sampling (h)
`
`JOB ratio
`JOB concen-
`tration in the Tumor/blood
`tumor
`
`30-50
`
`60min
`
`3-72
`
`Not given
`
`75
`
`1 mg/kg/min
`
`24
`
`12.2±
`4.8 µ,g/g
`
`2-5: 1
`(8-10: 1-1: 1)
`J.l ± 0.3
`
`Author
`
`Number
`of study
`patients
`
`Type of tumor
`
`24
`
`10
`
`61
`
`Haritz et al.,
`1994 [201
`Haselsberger
`et al., 1994
`[19]
`Stragliotto
`and
`Fankhauser,
`1995 [17]
`
`Glioblastoma
`multiforme
`Glioblastoma
`multiforme
`grade IV
`Various
`intracranial
`tumors
`
`Ceberg et al.,
`1995 [211
`Kageji T.,
`1997 [25]
`
`8
`
`123
`
`Horn ct al.,
`1998 [23]
`
`Goodman
`et al., 2000
`[24]
`
`IO
`
`19
`
`Summary
`
`255
`
`Astrocytoma
`grade III and IV
`Malignant
`glioma: low and
`high grade and
`others
`Glioblastoma
`multiforme and
`anaplastic
`astrocytoma
`Glioblastoma
`multiforme and
`anaplastic
`astrocytoma
`Various
`intracranial
`tumor entities
`
`10-100
`
`30min
`
`2-72
`
`50
`
`60min
`
`12-48
`
`HJ-50
`
`60-120min
`
`8.5-27
`
`25
`
`60min
`
`3-18
`
`0.2-4
`
`For 5mg
`B/kg at 18 h:
`Intracerebral
`tumor:
`2.l ±!ppm
`Extracerebral
`tumor:
`2.85 ±
`l.4ppm
`20 ± 4ppm
`after 12h
`IA: 26.8 ±
`19.5 µ,g/g
`IV: 20.9 ±
`12.2µg/g
`4.7-22.6 ~1g/g 0.3-3.4
`
`0.2-1.4
`
`IA: 1.77 ± 1.3
`IV: 1.3 ± 0.65
`
`26.5-88.2
`
`60min
`
`3-15
`
`<I: 4
`
`For 50mg
`B/kg: 11.9 ±
`6.1 µg/g
`
`10-100
`
`30-120min
`
`3-72
`
`IV: intravenous administration; IA: intra-arterial administration.
`
`interval was fixed by the protocol at 12 h. However,
`for patient treatment, based on all the information
`actually available, a time interval other than 12-14 h
`between BSH infusion and irradiation cannot be
`recommended.
`
`BSH uptake in the tumor
`
`A high degree of variability was detected in boron
`concentration, where several tumor samples could be
`obtained from 1 individual patient. This is in good
`
`agreement with most published data [19-22,24,25] and
`can be interpreted as an expression of the high degree of
`heterogeneity inside a tumor, i.e. a GBM. On the other
`hand, Horn et al. [23] reported quite small differences
`between maximum and average boron concentrations
`in the tumor tissue, indicating a more homogenous
`distribution of boron in the tumor. If the heterogeneity
`of data and the considerable SDs are taken into consid(cid:173)
`eration, it bec