Circulating tumor DNA as an early marker of therapeutic response in patients with metastatic colorectal cancer

BACKGROUND

Early indicators of treatment response in metastatic colorectal cancer (mCRC) could conceivably be used to optimize treatment. We explored early changes in circulating tumor DNA (ctDNA) levels as a marker of therapeutic efficacy.

PATIENTS AND METHODS

This prospective study involved 53 mCRC patients receiving standard first-line chemotherapy. Both ctDNA and CEA were assessed in plasma collected before treatment, 3 days after treatment and before cycle 2. Computed tomography (CT) scans were carried out at baseline and 8-10 weeks and were centrally assessed using RECIST v1.1 criteria. Tumors were sequenced using a panel of 15 genes frequently mutated in mCRC to identify candidate mutations for ctDNA analysis. For each patient, one tumor mutation was selected to assess the presence and the level of ctDNA in plasma samples using a digital genomic assay termed Safe-SeqS.

RESULTS

Candidate mutations for ctDNA analysis were identified in 52 (98.1%) of the tumors. These patient-specific candidate tissue mutations were detectable in the cell-free DNA from the plasma of 48 of these 52 patients (concordance 92.3%). Significant reductions in ctDNA (median 5.7-fold; P < 0.001) levels were observed before cycle 2, which correlated with CT responses at 8-10 weeks (odds ratio = 5.25 with a 10-fold ctDNA reduction; P = 0.016). Major reductions (≥10-fold) versus lesser reductions in ctDNA precycle 2 were associated with a trend for increased progression-free survival (median 14.7 versus 8.1 months; HR = 1.87; P = 0.266).

CONCLUSIONS

ctDNA is detectable in a high proportion of treatment naïve mCRC patients. Early changes in ctDNA during first-line chemotherapy predict the later radiologic response.

Wiki-based clinical practice guidelines for the management of adult onset sarcoma: a new paradigm in sarcoma evidence

In 2013 Australia introduced Wiki-based Clinical Practice Guidelines for the Management of Adult Onset Sarcoma. These guidelines utilized a customized MediaWiki software application for guideline development and are the first evidence-based guidelines for clinical management of sarcoma. This paper presents our experience with developing and implementing web-based interactive guidelines and reviews some of the challenges and lessons from adopting an evidence-based (rather than consensus-based) approach to clinical sarcoma guidelines. Digital guidelines can be easily updated with new evidence, continuously reviewed and widely disseminated. They provide an accessible method of enabling clinicians and consumers to access evidence-based clinical practice recommendations and, as evidenced by over 2000 views in the first four months after release, with 49% of those visits being from countries outside of Australia. The lessons learned have relevance to other rare cancers in addition to the international sarcoma community.

A phase Ib/II translational study of sunitinib with neoadjuvant radiotherapy in soft-tissue sarcoma

Background:

Preoperative radiotherapy (RT) is commonly used to treat localised soft-tissue sarcomas (STS). Hypoxia is an important determinant of radioresistance. Whether antiangiogenic therapy can ‘normalise' tumour vasculature, thereby improving oxygenation, remains unknown.

Methods:

Two cohorts were prospectively enrolled. Cohort A evaluated the implications of hypoxia in STS, using the hypoxic tracer ¹⁸F-azomycin arabinoside (FAZA-PET). In cohort B, sunitinib was added to preoperative RT in a dose-finding phase 1b/2 design.

Results:

In cohort A, 13 out of 23 tumours were hypoxic (FAZA-PET), correlating with metabolic activity (r²=0.85; P<0.001). Two-year progression-free (PFS) and overall (OS) survival were 61% (95% CI: 0.44–0.84) and 87% (95% CI: 0.74–1.00), respectively. Hypoxia was associated with radioresistance (P=0.012), higher local recurrence (Hazard ratio (HR): 10.2; P=0.02), PFS (HR: 8.4; P=0.02), and OS (HR: 41.4; P<0.04). In Cohort B, seven patients received sunitinib at dose level (DL): 0 (50 mg per day for 2 weeks before RT; 25 mg per day during RT) and two patients received DL: −1 (37.5 mg per day for entire period). Dose-limiting toxicities were observed in 4 out of 7 patients at DL 0 and 2 out of 2 patients at DL −1, resulting in premature study closure. Although there was no difference in PFS or OS, patients receiving sunitinib had higher local failure (HR: 8.1; P=0.004).

Conclusion:

In STS, hypoxia is associated with adverse outcomes. The combination of sunitinib with preoperative RT resulted in unacceptable toxicities, and higher local relapse rates.

Developing a national database for metastatic colorectal cancer management: perspectives and challenges

BACKGROUND

The changing treatment landscape for metastatic colorectal cancer creates multiple potential treatment strategies. An Australian-centric database capturing comprehensive information across a range of treatment locations would create a valuable resource enabling multiple important research questions to be addressed.

AIMS

To establish a collection of a consensus dataset capturing treatment and outcomes at multiple public and private hospitals across Australia.

METHODS

An electronic database was developed by a panel of clinicians, to capture an agreed dataset for patients with newly diagnosed metastatic colorectal cancer. Of particular interest were clinician decision-making, the impact of comorbidities and the frequency of major adverse events.

RESULTS

Since July 2009, data collection has been established at six public and eight private hospitals across three Australian states and territories. Successful linkage and analysis, with support from BioGrid Australia, of selected data on the initial 864 patients demonstrates that data can be captured from diverse sites, including public and private practice, that multiple factors impact on treatment delivered and outcomes achieved and that comprehensive data on rare but important adverse events can be captured. As a clinical research tool, the project has been highly successful, generating multiple presentations at national and international conferences related to a diverse range of research questions.

CONCLUSIONS

Multistate, project-specific data collection involving large numbers of patients is achievable. Providing invaluable insight into the routine clinical management of metastatic colorectal cancer in the era of targeted therapies, this also creates a significant resource for research, including many questions not being addressed by clinical trials.

Arterial blood pressure and vascular function in human saphenous vein

Hypertension is a risk factor for accelerated saphenous vein (SV) graft disease and endothelial dysfunction in a number of vascular territories. We examined the relationship between blood pressure (BP) and vascular function in SV from 94 male patients undergoing coronary artery bypass grafting (CABG). Patients were pretreated with respect to cholesterol (3.4±1.2 mmol/L) and BP (systolic 139±22 mmHg, diastolic 74±13 mmHg). All patients were taking aspirin, 85% statins, 50% angiotensin-converting enzyme inhibitors and 70% beta-blockers. We demonstrate in human SV rings ex vivo that increased BP has no effect on acetylcholine-mediated vasodilatation (p=0.58), nor on the constrictor response to L-NMMA (p=0.98), but has a positive association with the constrictor response to phenylephrine (p=0.008) and a negative correlation with the vasodilator response to sodium nitroprusside (p=0.03). These results may provide further explanation for the high incidence of early vein graft failure after CABG in hypertensive patients and support an aggressive approach to optimize BP before surgery.

Multicenter retrospective analysis of metastatic colorectal cancer (CRC) with high-level microsatellite instability (MSI-H)

BACKGROUND

The microsatellite instability-high (MSI-H) phenotype, present in 15% of early colorectal cancer (CRC), confers good prognosis. MSI-H metastatic CRC is rare and its impact on outcomes is unknown. We describe survival outcomes and the impact of chemotherapy, metastatectomy, and BRAF V600E mutation status in the largest reported cohort of MSI-H metastatic colorectal cancer (CRC).

PATIENTS AND METHODS

A retrospective review of 55 MSI-H metastatic CRC patients from two institutions, Royal Melbourne Hospital (Australia) and The University of Texas MD Anderson Cancer Center (United States), was conducted. Statistical analyses utilized Kaplan-Meier method, Log-rank test, and Cox proportional hazards models.

RESULTS

Median age was 67 years (20-90), 58% had poor differentiation, and 45% had stage IV disease at presentation. Median overall survival (OS) from metastatic disease was 15.4 months. Thirteen patients underwent R0/R1 metastatectomies, with median OS from metastatectomy 33.8 months. Thirty-one patients received first-line systemic chemotherapy for metastatic disease with median OS from the start of chemotherapy 11.5 months. No statistically significant difference in progression-free survival or OS was seen between fluoropyrimidine, oxaliplatin, or irinotecan based chemotherapy. BRAF V600E mutation was present in 14 of 47 patients (30%). BRAF V600E patients demonstrated significantly worse median OS; 10.1 versus 17.3 months, P = 0.03. In multivariate analyses, BRAF V600E mutants had worse OS (HR 4.04; P = 0.005), while patients undergoing metastatectomy (HR 0.11; P = <0.001) and patients who initially presented as stage IV disease had improved OS (HR 0.27; P = 0.003).

CONCLUSIONS

Patients with MSI-H metastatic CRC do not appear to have improved outcomes. BRAF V600E mutation is a poor prognostic factor in MSI-H metastatic CRC.

The effect of cyclosporin-A on peri-operative myocardial injury in adult patients undergoing coronary artery bypass graft surgery: a randomised controlled clinical trial

Objective

Cyclosporin-A (CsA) has been reported to reduce myocardial infarct size in both the experimental and clinical settings. This protective effect is dependent on its ability to prevent the opening of the mitochondrial permeability transition pore, a critical determinant of cell death in the setting of acute ischaemia-reperfusion injury. Whether CsA can reduce the extent of peri-operative myocardial injury (PMI) in patients undergoing coronary artery bypass graft (CABG) surgery is unknown, and is investigated in this randomised controlled clinical trial.

Methods

78 adult patients undergoing elective CABG surgery were randomised to receive either an intravenous bolus of CsA (2.5 mg/kg) or placebo administered after induction of anaesthesia and prior to sternotomy. PMI was assessed by measuring serum cardiac enzymes, troponin T (cTnT) and CK-MB at 0, 6, 12, 24, 48 and 72 h after surgery.

Results

There was no significant difference in mean peak cTnT levels between control (n=43) and CsA treatment (n=40) patients (0.56±0.06 ng/mL with control vs 0.35±0.05 ng/mL with CsA; p=0.07). However, in higher-risk patients with longer cardiopulmonary bypass times, there was a significant reduction in PMI with CsA therapy (p=0.049), with a reduced postoperative cTnT rise by 0.03 ng/mL for every 10 min, when compared with control.

Conclusions

In patients with longer cardiopulmonary bypass times, a single intravenous bolus of CsA administered prior to CABG surgery reduced the extent of PMI.

Different APC genotypes in proximal and distal sporadic colorectal cancers suggest distinct WNT/β-catenin signalling thresholds for tumourigenesis

Biallelic protein-truncating mutations in the adenomatous polyposis coli (APC) gene are prevalent in sporadic colorectal cancer (CRC). Mutations may not be fully inactivating, instead producing WNT/β-catenin signalling levels 'just-right' for tumourigenesis. However, the spectrum of optimal APC genotypes accounting for both hits, and the influence of clinicopathological features on genotype selection remain undefined. We analysed 630 sporadic CRCs for APC mutations and loss of heterozygosity (LOH) using sequencing and single-nucleotide polymorphism microarrays, respectively. Truncating APC mutations and/or LOH were detected in 75% of CRCs. Most truncating mutations occurred within a mutation cluster region (MCR; codons 1282-1581) leaving 1-3 intact 20 amino-acid repeats (20AARs) and abolishing all Ser-Ala-Met-Pro (SAMP) repeats. Cancers commonly had one MCR mutation plus either LOH or another mutation 5' to the MCR. LOH was associated with mutations leaving 1 intact 20AAR. MCR mutations leaving 1 vs 2-3 intact 20AARs were associated with 5' mutations disrupting or leaving intact the armadillo-repeat domain, respectively. Cancers with three hits had an over-representation of mutations upstream of codon 184, in the alternatively spliced region of exon 9, and 3' to the MCR. Microsatellite unstable cancers showed hyper-mutation at MCR mono- and di-nucleotide repeats, leaving 2-3 intact 20AARs. Proximal and distal cancers exhibited different preferred APC genotypes, leaving a total of 2 or 3 and 0 to 2 intact 20AARs, respectively. In conclusion, APC genotypes in sporadic CRCs demonstrate 'fine-tuned' interdependence of hits by type and location, consistent with selection for particular residual levels of WNT/β-catenin signalling, with different 'optimal' thresholds for proximal and distal cancers.

An initial watch and wait approach is a valid strategy for selected patients with newly diagnosed metastatic colorectal cancer

BACKGROUND

A range of treatments are available for patients with metastatic colorectal cancer (mCRC). An initial period without active treatment, a 'watch and wait approach', is variably employed in routine practice; however, there is no data to support this approach.

PATIENTS AND METHODS

We prospectively collected data regarding clinician treatment recommendations for patients with newly diagnosed mCRC in addition to subsequent treatment and outcomes. Follow-up and management was according to standard protocols.

RESULTS

Seven hundred and thirty-six patients (59.1% male, 40.9% female) with mCRC (January 2003-December 2010) were analysed; the median age was 67.9 years (range 26.2-95.5). Three hundred and seventy-seven patients (51.2%) received immediate chemotherapy. For 133 (18.1%), treatment was considered inappropriate. 34 patients (4.6%) declined therapy. For 192 (26.1%), a watch and wait policy was adopted and 168 (87.5%) of these received treatment, at a median of 3.7 months (range 2-35 months) from diagnosis. Compared with patients immediately treated, the number receiving all active chemotherapy agents (30.4 versus 39.3%) was similar and median survival (27 versus 17 months, P = 0.0008) was superior.

CONCLUSIONS

Our study demonstrates that a substantial minority of patients underwent an initial watch and wait approach. Ultimately, they received a similar treatment exposure to patients treated immediately and the survival outcomes were not compromised.

Prospective audit of mandibular fractures at the Charlotte Maxeke Johannesburg Academic Hospital

OBJECTIVE

This study was a prospective cross-sectional clinical audit of patients with mandibular fractures at the Charlotte Maxeke Johannesburg Academic Hospital.

METHODS

Between 1 March and 31 August 2004, patients with mandibular fractures seen by one clinician had their details recorded.

RESULTS

The female:male ratio of the study sample of 133 patients was 1:6. Seventy-seven per cent were aged 20-39 years. Most fractures (86%) were the result of interpersonal violence, and 65% were alcohol-associated. Open reduction (75%) was the most common treatment.

CONCLUSION

This study had the highest interpersonal violence and open reduction rates of all the studies reviewed.

Clinical and molecular characterization of a re-established line of sheep exhibiting hemophilia A

BACKGROUND

Large animal models that accurately mimic human hemophilia A (HA) are in great demand for developing and testing novel therapies to treat HA.

OBJECTIVES

To re-establish a line of sheep exhibiting a spontaneous bleeding disorder closely mimicking severe human HA, fully characterize their clinical presentation, and define the molecular basis for disease.

PATIENTS/METHODS

Sequential reproductive manipulations were performed with cryopreserved semen from a deceased affected ram. The resultant animals were examined for hematologic parameters, clinical symptoms, and responsiveness to human FVIII (hFVIII). The full coding region of sheep FVIII mRNA was sequenced to identify the genetic lesion.

RESULTS AND CONCLUSIONS

The combined reproductive technologies yielded 36 carriers and 8 affected animals. The latter had almost non-existent levels of FVIII:C and extremely prolonged aPTT, with otherwise normal hematologic parameters. These animals exhibited bleeding from the umbilical cord, prolonged tail and nail cuticle bleeding time, and multiple episodes of severe spontaneous bleeding, including hemarthroses, muscle hematomas and hematuria, all of which responded to hFVIII. Inhibitors of hFVIII were detected in four treated animals, further establishing the preclinical value of this model. Sequencing identified a premature stop codon and frame-shift in exon 14, providing a molecular explanation for HA. Given the decades of experience using sheep to study both normal physiology and a wide array of diseases and the high homology between human and sheep FVIII, this new model will enable a better understanding of HA and facilitate the development and testing of novel treatments that can directly translate to HA patients.

Phase I, pharmacokinetic, and pharmacodynamic evaluation of BNC105P, a novel anticancer agent that is both a vascular disrupting agent (VDA) and an inhibitor of cancer cell proliferation

e14512

Background: BNC105P is a novel anticancer agent that inhibits tubulin polymerization and acts as a VDA. BNC105P is a phosphorylated parent compound which rapidly becomes the active agent BNC105. BNC105 exhibits 100-fold specificity for activated endothelial cells compared to quiescent endothelial cells. Methods: BNC105P (2.1 to 18.9 mg/m2) was given IV over 10 min on day 1 and 8 every 21 days to patients (pts) with advanced solid tumors (ECOG 0–2) and adequate organ function. The objectives were to determine safety, tolerability, MTD and pharmacokinetics (PK). A pharmacodynamic response was evaluated using DCE-MRI with two baseline and two post dose assessments (3–6, 24 h). DLTs were determined during the first 21 days. Results: 9 pts (7 M; 2 F), median age 60 years have been enrolled with one pt each at 2.1 and 4.2 mg/m2. At 8.4 mg/m2, one pt experienced Grade 2 (Gr 2) mucositis and a switch to a ‘3+3’ design occurred. No DLTs have been observed in 3 pts at 12.6 mg/m2 and 1 pt at 18.9 mg/m2. Notable toxicity includes one episode of Gr 1 febrile episode possibly related to infusion, two episodes of Gr 1 fatigue and one Gr 1 rash. PK data of BNC105 indicates a linear increase in plasma AUC levels (Table) and plasma half life of < 0.5 h. Best observed responses were SD in 2/9 pts including one pt with mesothelioma (progression at entry) with SD up to week 22 (8.4 mg/m2). At doses ≥ 8.4 mg/m2, DCE-MRI images indicate changes in tumor perfusion post-dose. Two pts at 12.6 mg/m2 had a decrease in Ktrans values of 6 and 15 % compared to baseline. Conclusions: Pharmacodynamically active doses have been achieved with plasma drug levels correlating with active preclinical plasma exposure. To date, no excess toxicity has been observed at doses up to 18.9 mg/m2.

[Table: see text]

[Table: see text]

Adjuvant chemotherapy for stage II and stage III colon cancer—What is happening in routine practice?

e15046

Background: Randomised studies have defined adjuvant chemotherapy as standard treatment for stage III colon cancer (SIIICC), with multiple options available. For stage II (SII) disease, the selection of patients for adjuvant treatment remains controversial. There remains limited data on clinician decision making regarding adjuvant chemotherapy in routine clinical practice. Methods: A review of patients treated with SII & IIICC at 4 hospitals, utilising data from BioGrid Australia, where clinician choice and rationale were prospectively documented. Results: 372 patients (37%) with SII and 307 (30%) with SIIICC were identified from 1015 CC patients treated from January 2003 till November 2008. Median age was 68 years, 51% were male; 49% female. 66 (25%) of patients with SIIICC were not offered chemotherapy, predominantly due to advanced age or co-morbidity. Since oxaliplatin and capecitabine became widely available in 2005, 66% of treated patients have received oxaliplatin based therapy, 15% bolus 5-FU alone and 19% capecitabine. For SII disease, overall 81 (26%) pts received adjuvant chemotherapy. Age was the dominant influence on treatment choice with 41% aged 70 (p<0.001) receiving treatment. Patients with high risk features were also more likely to receive adjuvant therapy. (p= 0.006 for those with lymphovascular invasion and p= 0.0068 for those with T4 tumours). Dose reductions and completion rates were similar for SII and III disease, and for older and younger patients. Conclusions: Over 25% of patients with SIIICC do not receive adjuvant chemotherapy in routine practice, with physicians basing non-treatment recommendations predominantly on patient age and co-morbidity. Where treatment is used, oxaliplatin-based therapy is the dominant regimen, except in older patients. In SIICC, adjuvant chemotherapy is used in one in four patients, more frequently in younger patients and those with high risk features.

No significant financial relationships to disclose.

Selecting subjects for a therapeutic target in colorectal cancer (CRC): Using a clinical database to enrich for patients harboring the BRAFV600E mutation

11003

Introduction: The BRAFV600E mutation (BRAF) causes constitutive activation of the RAS-induced MAPK pathway and is found in 10% of colon cancers. B-RAF inhibitors are in early clinical development, but their development in CRC will be challenging unless subsets of patients (pts) with higher rates of BRAF can be defined. The mutation rate in rectal tumors, the concordance between primary and metastases, and the prognostic/predictive significance of BRAF are current gaps in knowledge. Methods: 481 primary tumors and 80 matched primary-metastasis (prim-met) pairs were analysed from a pre-defined cohort of pts with CRC based on age (≥ 70 vs < 70 years), gender, tumor site (right-R, left-L and rectum), stage (A to C vs D) and ≥ 2 years follow-up. BRAF was assessed by routine sequencing of exon 15 and by a mutant-specific PCR assay. KRAS (KRAS-codon 12 and 13) and MSI (Bethesda markers) status were also examined. Results: Overall prevalence of BRAF was 11%. BRAF (see table ) was independently associated with increasing age, female gender and R-sided cancer, but not with stage. Mutations were rare in rectal cancers. BRAF was associated with inferior overall survival in stage D pts (log-rank, p = 0.0003; HR 0.38, 95% CI, 0.10–0.51). Survival analysis will be further stratified by treatment received. No difference in outcome was seen in preliminary analysis of earlier stage cancers. Mutation frequencies in the prim-met pairs were 38% (30/80) and 1.3% (1/80) for KRAS and BRAF, respectively. Overall concordance was 88% (70/80) for KRAS and 100% (80/80) for BRAF status. Conclusions: The development of selective B-Raf inhibitors in CRC is potentially more attractive due to the ability to define patient subsets with a higher prevalence of BRAF mutations. Analysis of the primary tumor reliably predicts the status of metastatic disease in the same patient. The association between BRAFand poor outcome will need to be considered when interpreting the result of studies targeting this mutation. [Table: see text]

[Table: see text]

A randomized, placebo-controlled study of the effects of naproxen, aspirin, celecoxib or clopidogrel on gastroduodenal mucosal healing

BACKGROUND

Many individuals with gastroduodenal ulcers require on-going, non-steroidal anti-inflammatory drug (NSAID) or anti-platelet therapy.

AIMS

To evaluate the effects of these agents on gastroduodenal mucosal healing.

METHODS

Helicobacter pylori-negative volunteers were randomized to receive naproxen, celecoxib, aspirin, clopidogrel or placebo. Antral and duodenal lesions were created endoscopically with a biopsy forceps. After 7 days of medication dosing, each lesion was scored [from 0 (low) to 8 (high)] using a validated methodology. The primary endpoint was the mean injury score. The secondary endpoint was the percentage of subjects with > or = 1 unhealed lesion.

RESULTS

In all, 108 subjects completed the study. Naproxen impaired antral lesion healing more than placebo, clopidogrel, aspirin or celecoxib (mean injury score of 4.3 vs. 3.0, 2.7, 3.2, and 3.2, respectively, P < 0.05). Naproxen impaired duodenal lesion healing more than placebo, clopidogrel or aspirin (mean injury score of 4.0 vs. 2.4, 2.6, and 2.2, respectively, P < 0.05). More subjects taking naproxen than placebo or clopidogrel had > or =1 unhealed antral lesions (72.2% vs. 36.0% and 32.0%, respectively, P < 0.05) and unhealed duodenal lesions (61.1% vs. 16.0% and 28.0%, respectively, P < 0.05).

CONCLUSIONS

Naproxen may impair gastroduodenal healing more than aspirin or celecoxib in H. pylori negative subjects. Clopidogrel did not impair mucosal healing.

Unusual neurologic manifestations (I): Parkinsonism in juvenile SLE

A girl with neuropsychiatric lupus demonstrated Parkinsonian features soon after commencing risperidone. The single photon emission computed tomography scan showed hyperperfusion of the basal ganglia. Symptoms abated with the addition of dopaminergic agents to immunosuppressive therapy. The literature on juvenile Parkinsonism in lupus has been reviewed.

Inflammatory dentigerous cyst in a 3 year old South African black male: A case report

We present here a case of a dentigerous cyst in the anterior maxilla of a 3 year old male. There was associated cortical expansion and facial asymmetry. These cysts are rare at this age and in addition are less common in the maxilla. Management consisted of enucleation under general anaesthetic including removal of the unerupted 11. This report attempts to highlight the importance of prompt diagnosis and referral of children with dentigerous cysts.

Characterization of polymeric dispersions of dimenhydrinate in ethyl cellulose for controlled release

Granulations of dimenhydrinate (DMH) were prepared using various concentrations of ethyl cellulose (EC) by the solid dispersion technique. Characterization was done using thermal analysis, powder X-ray diffraction, infrared spectroscopy, optical microscopy and dissolution studies. Humidity studies were performed to investigate the effect of moisture on the drug and solid dispersions. It was seen that the crystalline drug was converted into its amorphous form in all the granulations. There was no chemical interaction between the DMH and EC. The thermal decomposition of drug in the granules was not affected. Dissolution studies revealed that the drug release from the granulations was significantly reduced as compared to the pure drug. As the amount of ethyl cellulose increased, the drug release rate decreased and the drug release kinetics showed a better fit to zero-order kinetics. Humidity studies showed that the drug and granulations remained stable in conditions not exceeding 70%RH. At high humidity of 100%RH, there was formation of the hydrate crystal forms of the drug in the pure drug samples and granules with 1:1 DMH-EC content whereas the granules with higher polymer content did not show any significant changes indicating better drug stability in the granules.