Carrageenan nasal spray in virus confirmed common cold: individual patient data analysis of two randomized controlled trials

Background

Clinical trials applying iota-carrageenan nasal spray have previously shown to reduce duration of virus-confirmed common cold. The present study pooled data of two similar clinical trials to provide further evidence for the antiviral effectiveness of carrageenan.

Methods

Individual patient data were analyzed from two randomized double blind placebo controlled trials assessing the therapeutic effectiveness of carrageenan nasal spray in acute common cold. Patients with virus-confirmed common cold (n = 254, verum 126, placebo 128) were included and the following parameters were appraised: duration of disease, number of patients with relapses, number of respiratory viruses and viral titers at inclusion (visit 1) compared to days 3–5 (visit 2).

Results

Carrageenan treated patients showed a significant reduction in duration of disease of almost 2 days (p < 0.05) as well as significantly fewer relapses during 21 days of observation period (p < 0.05). The virus clearance between visit 1 and visit 2 was significantly more pronounced in the carrageenan group (p < 0.05). In both studies, virus-confirmed common cold was caused by three main virus subtypes: human rhinovirus (46%), human coronavirus (25%) and influenza A (14%) virus. Carrageenan nasal spray showed significant antiviral efficacy in all three virus subgroups, the highest effectiveness was observed in human corona virus-infected patients. The reduced duration of disease was 3 days (p < 0.01) and the number of relapses was three times less (p < 0.01) in carrageenan treated corona-virus-infected patients compared to control patients.

Conclusions

Administration of carrageenan nasal spray in children as well as in adults suffering from virus-confirmed common cold reduced duration of disease, increased viral clearance and reduced relapses of symptoms. Carrageenan nasal spray appeared as an effective treatment of common cold in children and adults.

Trial registration

Pooled data from ISRCTN52519535 and ISRCTN80148028

A certified plasmid reference material for the standardisation of BCR-ABL1 mRNA quantification by real-time quantitative PCR

Serial quantification of BCR–ABL1 mRNA is an important therapeutic indicator in chronic myeloid leukaemia, but there is a substantial variation in results reported by different laboratories. To improve comparability, an internationally accepted plasmid certified reference material (CRM) was developed according to ISO Guide 34:2009. Fragments of BCR–ABL1 (e14a2 mRNA fusion), BCR and GUSB transcripts were amplified and cloned into pUC18 to yield plasmid pIRMM0099. Six different linearised plasmid solutions were produced with the following copy number concentrations, assigned by digital PCR, and expanded uncertainties: 1.08±0.13 × 10⁶, 1.08±0.11 × 10⁵, 1.03±0.10 × 10⁴, 1.02±0.09 × 10³, 1.04±0.10 × 10² and 10.0±1.5 copies/μl. The certification of the material for the number of specific DNA fragments per plasmid, copy number concentration of the plasmid solutions and the assessment of inter-unit heterogeneity and stability were performed according to ISO Guide 35:2006. Two suitability studies performed by 63 BCR–ABL1 testing laboratories demonstrated that this set of 6 plasmid CRMs can help to standardise a number of measured transcripts of e14a2 BCR–ABL1 and three control genes (ABL1, BCR and GUSB). The set of six plasmid CRMs is distributed worldwide by the Institute for Reference Materials and Measurements (Belgium) and its authorised distributors (https://ec.europa.eu/jrc/en/reference-materials/catalogue/; CRM code ERM-AD623a-f).

Development of treatment and clinical results in childhood AML in Austria (1993-2013)

Background

Since the early 1990s, three consecutive pediatric acute myeloid leukemia (AML) trials have been performed in Austria (AML-Berlin-Frankfurt-Münster (BFM) 93, AML-BFM 98, and AML-BFM 2004) in close cooperation with the international BFM study center. Herein, we review the pertinent patient characteristics, therapy, and outcome data.

Patients and methods

From January 1993 to April 2013, 249 children and adolescents (193 protocol patients) diagnosed with AML were enrolled in the three BFM studies. Patients were mainly treated in one of five pediatric hematology/oncology centers distributed over Austria.

Results

Many characteristics and outcome parameters were not statistically different between the three trials. Almost similar proportions of patients were stratified into two risk groups: standard risk (SR) (approximately 37 % overall) and high-risk (HR) (61 %). MLL rearrangements were found in 23 % of patients overall as the most frequent genetic aberration subtype. Complete remission (CR) was achieved by 84-95 % of patients. The most important type of event was leukemic relapse (5-year cumulative incidence 40 ± 8 %, 21 ± 5 %, and 39 ± 6 %; p = 0.058), with a trend to a higher rate specifically in SR patients of study AML-BFM 2004 compared with AML-BFM 98. Importantly, the frequency of death from causes other than relapse sequelae declined over the years (AML-BFM 93: 5/42 12 %, AML-BFM 98: 5/57 9 %, and AML-BFM 2004: 5/94 5 %). Altogether, event-free survival at 5 years varied insignificantly (48 ± 8 %, 61 ± 7 %, and 50 ± 6 %; p = 0.406). Nevertheless, survival (pSU) apparently improved from BFM 93 to subsequent studies, both overall (57 ± 8 %, 75 ± 6 %, and 62 ± 6 %; p = 0.046) and regarding the HR group (5-year-probability of survival (pSU) 40 ± 10 %, 66 ± 8 %, and 52 ± 8 %; p = 0.039).

Conclusion

Treatment of pediatric AML in Austria renders survival rates in the range of international best practice. However, unambiguous statistical comparison of treatment periods is eventually hampered by small numbers and inequalities of recruitment. Hence, only internationally collaborative trials will allow developing treatment further to achieve higher cure rates with fewer events.

Identification of Ponatinib as a potent inhibitor of growth, migration, and activation of neoplastic eosinophils carrying FIP1L1-PDGFRA

In chronic eosinophilic leukemia, the transforming oncoprotein FIP1L1-PDGFRA is a major target of therapy. In most patients, the tyrosine kinase inhibitor (TKI) imatinib induces complete remission. For patients who are intolerant or resistant, novel TKIs have been proposed. We examined the in vitro effects of 14 kinase blockers on growth and function of EOL-1 cells, a FIP1L1-PDGFRA(+) eosinophil cell line. Major growth-inhibitory effects were seen with all PDGFR-blocking agents, with IC50 values in the low nanomolar range: ponatinib, 0.1-0.2 nmol/L; sorafenib, 0.1-0.2 nmol/L; masitinib, 0.2-0.5 nmol/L; nilotinib, 0.2-1.0 nmol/L; dasatinib, 0.5-2.0 nmol/L; sunitinib, 1-2 nmol/L; midostaurin, 5-10 nmol/L. These drugs were also found to block activation of PDGFR-downstream signaling molecules, including Akt, S6, and STAT5 in EOL-1 cells. All effective TKIs produced apoptosis in EOL-1 cells as determined by microscopy, Annexin-V/PI, and caspase-3 staining. In addition, PDGFR-targeting TKIs were found to inhibit cytokine-induced migration of EOL-1 cells. In all bioassays used, ponatinib was found to be the most potent compound in EOL-1 cells. In addition, ponatinib was found to downregulate expression of the activation-linked surface antigen CD63 on EOL-1 cells and to suppress the growth of primary neoplastic eosinophils. We also examined drug effects on Ba/F3 cells expressing two clinically relevant, imatinib-resistant, mutant forms of FIP1L1-PDGFRA, namely T674I and D842V. Strong inhibitory effects on both mutants were seen only with ponatinib. In summary, novel PDGFR-targeting TKIs may be alternative agents for the treatment of patients with imatinib-resistant chronic eosinophilic leukemia. Although several different PDGFR-targeting agents are effective, the most potent drug appears to be ponatinib.

Post-transplant monitoring of chimerism by lineage-specific analysis

Molecular surveillance of hematopoietic chimerism is an important part of the routine diagnostic program in patients after allogeneic stem cell transplantation. Chimerism testing permits early prediction and documentation of successful engraftment and facilitates early risk assessment of impending graft rejection. In patients transplanted for treatment of malignant hematologic disorders, monitoring of chimerism can provide an early indication of incipient disease relapse. The investigation of chimerism has therefore become an indispensable tool for the management of patients during the post-transplant period. Increasing use of reduced-intensity conditioning, which is associated with prolonged duration of mixed hematopoietic chimerism, has further increased the clinical importance of chimerism analysis. At present, the most commonly used technical approach to the investigation of chimerism is microsatellite analysis by polymerase chain reaction. The investigation of chimerism within specific leukocyte subsets isolated from peripheral blood or bone marrow samples by flow sorting- or magnetic bead-based techniques provides more specific information on processes underlying the dynamics of donor/recipient chimerism. Moreover, cell subset-specific analysis permits the assessment of impending complications at a significantly higher sensitivity, thus providing a basis for earlier treatment decisions.

Rapid identification of compound mutations in patients with Philadelphia-positive leukaemias by long-range next generation sequencing

An emerging problem in patients with Philadelphia (Ph)-positive leukaemias is the occurrence of cells with multiple mutations in the BCR-ABL1 tyrosine kinase domain (TKD) associated with high resistance to different tyrosine kinase inhibitors. Rapid and sensitive detection of leukaemic subclones carrying such changes, referred to as compound mutations, is therefore of increasing clinical relevance. However, current diagnostic methods including next generation sequencing (NGS) of short fragments do not optimally meet these requirements. We have therefore established a long-range (LR) NGS approach permitting massively parallel sequencing of the entire TKD length of 933bp in a single read using 454 sequencing with the GS FLX+ instrument (454 Life Sciences). By testing a series of individual and consecutive specimens derived from six patients with chronic myeloid leukaemia, we demonstrate that long-range NGS analysis permits sensitive identification of mutations and their assignment to the same or to separate subclones. This approach also facilitates readily interpretable documentation of insertions and deletions in the entire BCR-ABL1 TKD. The long-range NGS findings were reevaluated by an independent technical approach in select cases. Polymerase chain reaction (PCR) amplicons of the BCR-ABL1 TKD derived from individual specimens were subcloned into pGEM®-T plasmids, and >100 individual clones were subjected to analysis by Sanger sequencing. The NGS results were confirmed, thus documenting the reliability of the new technology. Long-range NGS analysis therefore provides an economic approach to the identification of compound mutations and other genetic alterations in the entire BCR-ABL1 TKD, and represents an important advancement of the diagnostic armamentarium for rapid assessment of impending resistant disease.

[Current diagnostic requirements in chronic myeloid leukemia]

In patients with chronic myeloid leukemia, high-quality diagnostics is of paramount importance for the surveillance of treatment efficacy. The availability of new tyrosine kinase inhibitors providing more rapid and deeper responses requires the employment of standardized and highly sensitive diagnostic methods to ensure optimal monitoring of the patients. This review presents the current international diagnostic standards and the certified laboratories in Austria.

Diagnosis and treatment of adenovirus infection in immunocompromised patients

In immunocompromised patients, human adenovirus (HAdV) infections can cause life-threatening multiorgan disease. This review summarizes the incidence and risk factors of invasive human adenovirus infections in immunocompromised patients as well as the recently developed standards for diagnostic methods and strategies according to the predominant risk factors in adults and children. Recommendations for preemptive and therapeutic treatment strategies and the outcome in different risk groups are presented. Novel therapeutic approaches including CMX001, a new orally bioavailable lipid conjugate of cidofovir and the transfer of adenovirus-specific donor T cells in the context of allogeneic stem cell transplantation are discussed.

Combinatorial targeting of 2 different steps in adenoviral DNA replication by herpes simplex virus thymidine kinase and artificial microRNA expression for the inhibition of virus multiplication in the presence of ganciclovir

BACKGROUND

Human adenoviruses are a frequent threat to immunocompromised patients, and disseminated disease is associated with severe morbidity and mortality. Current drugs are not capable of preventing all fatalities, thus indicating the need for alternative treatment strategies. Adenoviruses can be rendered susceptible to antiherpetic prodrugs such as ganciclovir (GCV), upon expression of the herpes simplex virus thymidine kinase (HSV-TK) gene in adenovirus-infected cells. Furthermore, adenoviruses are amenable to post-transcriptional gene silencing via small interfering RNAs (siRNAs) or artificial micro RNAs (amiRNAs).

RESULTS

In this study, we combined these 2 approaches by constructing a combinatorial gene expression cassette that comprises the HSV-TK gene and multiple copies of an amiRNA directed against the mRNA encoding the adenoviral preterminal protein (pTP). HSV-TK gene expression was controlled by the adenoviral E4 promoter, which is activated in the presence of the adenoviral E1 gene products (i.e., when adenovirus is present in the cell). When inserted into a replication-deficient (E1-, E3-deleted) adenoviral vector, this cassette effectively inhibited the replication of wild-type adenovirus in vitro. The reduction rate mediated by the combinatorial approach was higher compared to that achieved by either of the 2 approaches alone, and these obvious additive effects became most pronounced when the GCV concentration was low.

CONCLUSIONS

The concept presented here has the potential to aid in the inhibition of wild-type adenovirus replication. Furthermore, the combinatorial expression cassette may constitute a safeguard to potentially control unintended replication of adenoviral vectors and to prevent immune responses provoked by them.

Species-specific identification of a wide range of clinically relevant fungal pathogens by the Luminex(®) xMAP technology

Invasive fungal infections (IFI) are a common cause of life-threatening events in immunocompromised patients. Early detection and identification of the fungal pathogen is an important prerequisite for timely onset of the most appropriate treatment. Methods based on fungal culture are often too slow to be clinically useful. Other approaches to the identification of fungal species, including molecular techniques, are often restricted to a small number of the most commonly occurring pathogens and are therefore of limited use in the clinical setting. The development of assays for the detection and identification of a broad-range of clinically relevant fungal species is therefore an urgently needed step towards optimized diagnostics of IFI.The Luminex(®) xMAP technology offers a platform for the establishment of multiplex assays permitting high-throughput analysis of up to 100 different target molecules in a single test. Here we describe a Luminex(®)-based multiplex assay permitting rapid detection and identification of 10 fungal genera and 29 different species, including both commonly occurring and emerging fungal pathogens.

Stem cell transplantation after reduced-intensity conditioning for sickle cell disease

Sickle cell disease (SCD) is still associated with substantial morbidity and reduced life expectancy. Disease-related mortality rises to 14% in adolescents and young adults. Overall and disease-free survival following haematopoietic stem cell transplantation (HSCT) is 90% and 95%, respectively. To reduce transplant-associated late effects, the feasibility of a highly immunosuppressive reduced-intensity conditioning (RIC) regimen was explored in children with SCD and a matched sibling donor. Eight patients (median age, 9 yr) and symptomatic SCD were included. The conditioning regimen consisted of fludarabine, melphalan and either thiotepa or total lymphoid irradiation plus antithymocyte globuline or alemtuzumab. The graft was bone marrow in seven and cord blood in one case. The conditioning regimen was well tolerated and no severe infectious complications occurred. All patients displayed mixed chimaerism on day +28. After a median follow-up of 4 yr, 3/8 patients have mixed leucocyte chimaerism and 8/8 patients have 100% donor erythropoiesis. HSCT from matched sibling donors following a RIC regimen was well tolerated and resulted in cure in all patients studied. If confirmed in larger patient cohorts, these observations will have important implications for the indications of HSCT in children with SCD.

An adenoviral vector-based expression and delivery system for the inhibition of wild-type adenovirus replication by artificial microRNAs

Human adenoviruses are rarely associated with life-threatening infections in healthy individuals. However, immunocompromised patients, and particularly allogeneic hematopoietic stem cell transplant recipients, are at high risk of developing disseminated and potentially fatal disease. The efficacy of commonly used drugs to treat adenovirus infections (i.e., cidofovir in most cases) is limited, and alternative treatment options are needed. Artificial microRNAs (amiRNAs) are a class of synthetic RNAs resembling cellular miRNAs, and, similar to their natural relatives, can mediate the knockdown of endogenous gene expression. This process, termed RNA interference, can be harnessed to target and potentially silence both cellular and viral genes. In this study, we designed amiRNAs directed against adenoviral E1A, DNA polymerase, and preterminal protein (pTP) mRNAs in order to inhibit adenoviral replication in vitro. For the expression of amiRNA-encoding sequences, we utilized replication-deficient adenoviral vectors. In cells transduced with the recombinant vectors and infected with the wild-type (wt) adenovirus, one particular amiRNA that was directed against the pTP mRNA was capable of decreasing the output of infectious wt virus progeny by 2.6 orders of magnitude. This inhibition rate could be achieved by concatemerizing amiRNA-encoding sequences to allow for high intracellular amiRNA concentrations. Because superinfecting wt virus induces the replication and amplification of the recombinant adenoviral vector, amiRNA concentrations were increased in cells infected with wt adenovirus. Furthermore, a combination of amiRNA expression and treatment of infected cells with cidofovir resulted in additive effects that manifested as a total reduction of infectious virus progeny by greater than 3 orders of magnitude.

Targeted expression of herpes simplex virus thymidine kinase in adenovirus-infected cells reduces virus titers upon treatment with ganciclovir in vitro

BACKGROUND

Adenoviruses are a frequent cause of life-threatening infections in immunocompromised patients. Available therapeutics still cannot completely prevent fatal outcomes. By contrast, herpes viruses are well treatable with prodrugs such as ganciclovir (GCV), which are selectively activated in virus-infected cells by virus-encoded thymidine kinases. This effective group of prodrugs is not applicable to adenoviruses and other DNA viruses because they lack those kinases.

METHODS

To render adenoviruses amenable to GCV treatment, we generated an adenoviral vector-based delivery system for targeted expression of herpes simplex virus thymidine kinase (HSV-TK) in wild-type adenovirus 5 (wt Ad5)-infected cells. HSV-TK expression was largely restricted to wt virus-infected cells by transcription of the gene from the Ad5 E4 promoter. Its activity is dependent on the adenoviral E1A gene product which is not produced by the vector but is only provided in cells infected with wt adenovirus. The anti-adenoviral effect of HSV-TK expression and concomitant treatment with GCV was assessed in vitro in four different cell lines or primary cells.

RESULTS

E4 promoter-mediated HSV-TK background expression was sufficiently low to prevent cytotoxicity in the presence of low-levels GCV in cells not infected with wt Ad5. However, expression was several-fold increased in wt Ad5-infected cells and treatment with low levels of GCV efficiently inhibited wt Ad5 DNA replication. Genome copy numbers and output of infectious particles were reduced by up to > 99.99% and cell viability was greatly increased.

CONCLUSIONS

We extended the concept of enzyme/prodrug therapy to adenovirus infections by selectively sensitizing adenovirus-infected cells to treatment with GCV.

Lessons learned from a double-blind randomised placebo-controlled study with a iota-carrageenan nasal spray as medical device in children with acute symptoms of common cold

Background

Common cold is caused by a variety of respiratory viruses. The prevalence in children is high, and it potentially contributes to significant morbidity. Iota-carragenan, a polymer derived from red seaweed, has reduced viral load in nasal secretions and alleviated symptoms in adults with common cold.

Methods

We have assessed the antiviral and therapeutic activity of a nasal spray containing iota-carrageenan in children with acute symptoms of common cold. A cohort of 153 children between 1–18 years (mean age 5 years), displaying acute symptoms of common cold were randomly assigned to treatment with a nasal spray containing iota-carrageenan (0.12%) as verum or 0.9% sodium chloride solution as placebo for seven days. Symptoms of common cold were recorded and the viral load of respiratory viruses in nasal secretions was determined at two consecutive visits.

Results

The results of the present study showed no significant difference between the iota carrageenan and the placebo group on the mean of TSS between study days 2–7. Secondary endpoints, such as reduced time to clearance of disease (7.6 vs 9.4 days; p = 0.038), reduction of viral load (p = 0.026), and lower incidence of secondary infections with other respiratory viruses (p = 0.046) indicated beneficial effects of iota-carrageenan in this population. The treatment was safe and well tolerated, with less side effects observed in the verum group compared to placebo.

Conclusion

In this study iota-carrageenan did not alleviate symptoms in children with acute symptoms of common cold, but significantly reduced viral load in nasal secretions that may have important implications for future studies.

Trial registration

ISRCTN52519535, http://www.controlled-trials.com/ISRCTN52519535/

Molecular diagnosis and management of viral infections in hematopoietic stem cell transplant recipients

Viral infections after allogeneic hematopoietic stem cell transplantation (HSCT) are important complications associated with high morbidity and mortality. In this setting, reactivations of persisting latent viral pathogens from donor and/or recipient cells play a central role whereas the sterile environment of transplant units renders new infections less likely. The viruses currently regarded as most relevant in the HSCT setting include particularly the herpes virus family--specifically cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus 6 (HHV-6)--as well as human adenoviruses (AdVs) and the polyoma virus BK (BKV). Timely detection and monitoring of virus copy numbers are prerequisites for successful preemptive treatment approaches. Pre- and post-transplant surveillance by sensitive and quantitative molecular methods has therefore become an essential part of the diagnostic routine. In this review, we discuss diagnostic aspects and the clinical management of the most important viral infections in HSCT recipients, with a focus on pediatric patients.

Prevalence and clinical course of viral upper respiratory tract infections in immunocompromised pediatric patients with malignancies or after hematopoietic stem cell transplantation

BACKGROUND

Respiratory tract infections (RTI) in immunosuppressed pediatric patients with malignancies or after hematopoietic stem cell transplantation (HSCT) are associated with significant morbidity and mortality. Prospective data on the incidence and clinical role of infections by respiratory viruses in this population have been lacking.

METHODS

In this prospective study, 191 children between 0 and 18 years of age were investigated by real-time polymerase chain reaction for the presence of 8 common respiratory virus types in transnasal aspirations. The study included 110 children with leukemia, lymphoma, or solid tumors (subgroup 1); 31 children after HSCT (subgroup 2); and 50 immunocompetent control patients.

RESULTS

In comparison with the control group, immunocompromised children showed a significantly higher incidence of positive virus tests (subgroup 1: 53%; subgroup 2: 81%; controls: 24%; P<0.0001), and more frequently experienced ensuing viral infections in the lower respiratory tract (subgroup 1: 74%; subgroup 2: 88%; controls: 25%; P<0.0001). Sixteen percent of these children had coinfections by 2 or more viruses and revealed more severe respiratory illness.

CONCLUSIONS

The present epidemiologic study on viral upper RTI in immunocompromised children revealed a high virus-associated morbidity which was particularly prominent in HSCT recipients. In these children, detection of viral coinfections was identified as a risk factor for a severe course of lower RTI.

High-dose imatinib induction followed by standard-dose maintenance in pre-treated chronic phase chronic myeloid leukemia patients--final analysis of a randomized, multicenter, phase III trial

BACKGROUND

Previous data suggest that the response of chronic myeloid leukemia cells to imatinib is dose-dependent. The potential benefit of initial dose intensification of imatinib in pre-treated patients with chronic phase chronic myeloid leukemia remains unknown.

DESIGN AND METHODS

Two hundred and twenty-seven pre-treated patients with chronic myeloid leukemia in chronic phase were randomly assigned to continuous treatment with a standard dose of imatinib (400 mg/day; n=113) or to 6 months of high-dose induction with imatinib (800 mg/day) followed by a standard dose of imatinib as maintenance therapy (n=114).

RESULTS

The rates of major and complete cytogenetic responses were significantly higher in the high-dose arm than in the standard-dose arm at both 3 and 6 months (major cytogenetic responses: 36.8% versus 21.2%, P=0.01 and 50.0% versus 34.5%, P=0.018; complete cytogenetic responses: 22.8% versus 6.2%, P<0.001 and 40.4% versus 16.8%, P<0.001) on the basis of an intention-to-treat analysis. At 12 months, the difference between treatment arms remained statistically significant for complete cytogenetic responses (40.4% versus 24.8%, P=0.012) but not for major cytogenetic responses (49.1% versus 44.2%, P=0.462). The rate of major molecular responses was also significantly better at 3 and 6 months in the high-dose arm (month 3: 14.9% versus 3.5%, P=0.003; month 6: 32.5% versus 8.8%, P<0.001). Overall and progression-free survival rates were comparable between arms, but event-free survival was significantly worse in the high-dose arm (P=0.014).

CONCLUSIONS

Standard-dose imatinib remains the standard of care for pre-treated patients with chronic phase chronic myeloid leukemia (Clinicaltrials.gov identifier: NCT00327262).

Nilotinib as frontline and second-line therapy in chronic myeloid leukemia: open questions

Nilotinib is a second generation ABL tyrosine kinase inhibitor (TKI) that exerts major anti-leukemic effects in newly diagnosed patients with chronic myeloid leukemia (CML) as well as in most patients with imatinib-resistant CML. In freshly diagnosed patients, the anti-leukemic activity of nilotinib exceeds the efficacy of imatinib, and although long-term data for nilotinib are not available yet, the drug has recently been approved for firstline treatment of chronic phase CML in various countries. Still however, several questions concerning the optimal dose, follow-up parameters, long-term safety, and patient selection remain open. Likewise, it remains uncertain whether both Sokal low-risk and high-risk patients should receive nilotinib as frontline therapy in the future. Another question is whether nilotinib can completely eradicate CML in a subset of patients. Furthermore, it remains unclear whether and what comorbidity must be regarded as relative or absolute contra-indication for this TKI. To discuss these issues, the Austrian CML Working Group organized a series of meetings in 2010. In the current article, the outcomes from these discussions are summarized and presented together with recommendations for frontline use of TKIs in various groups of patients with CML. These recommendations should assist in daily practice as well as in the preparation and conduct of clinical trials.