***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: To compare the effectiveness and safety of controlled-release ( CR ) oxycodone tablets with immediate-release ( IR ) oxycodone in patients with chronic cancer pain , a multicenter , r and omized , double-blind , parallel-group study was performed in 111 patients with cancer pain . Patients were treated with 6 to 12 tablets or capsules of fixed-combination opioid/nonopioid analgesics per day at study entry . Patients received 30 mg of CR oxycodone tablets every 12 hr or 15 mg of IR oxycodone four times daily for 5 days . No titration or supplemental analgesic medications were permitted . The mean ( + /- SE ) baseline pain intensity ( 0 = none , 1 = slight , 2 = moderate , 3 = severe ) was 1.5 + /- 0.1 for the CR oxycodone-treated group and 1.3 + /- 0.1 for the group given IR oxycodone ( P > 0.05 ) . The 5-day mean pain intensity was 1.4 + /- 0.1 and 1.1 + /- 0.1 for the CR and IR groups , respectively ( P > 0.05 ) . Discontinuation rates were equivalent ( 33 % ) . There was no significant difference between treatment groups in the incidence of adverse events . This study demonstrates that cancer pain patients given 6 to 12 tablets or capsules of fixed-dose combination analgesics can be equally well treated with CR oxycodone administered every 12 hr or IR oxycodone four times daily at the same total daily dose . CR oxycodone offers the benefits of twice daily dosing Morphine and oxycodone were administered to ten patients suffering from severe cancer pain in a double-blind cross-over study . The patients titrated themselves pain-free , first intravenously , using a patient-controlled analgesia device , and then orally . Each titration phase lasted for 48 hours . Blood sample s were drawn after 36 hr of each administration phase . The plasma levels of morphine , morphine-6- and morphine-3 glucoronides were determined with high performance liquid chromatography ( HPLC ) , whereas the oxycodone sample s were assayed with gas chromatography ( GC ) . Twin sample s were analyzed for plasma opioid activity with a radioreceptor assay ( RRA ) using 3H-dihydromorphine and 3H-naloxone as radiolig and s. Adequate analgesia was achieved with both morphine and oxycodone . About 30 % more oxycodone was needed intravenously , whereas 25 % less oxycodone than morphine was consumed orally . There was a good linear correlation between the morphine concentrations measured with HPLC and RRA . The mean morphine-6-glucuronide to morphine concentration ratio was 2.3 after intravenous and 4.6 after oral administration . Results from RRA indicate that oxycodone in vivo is a potent mu-agonist and that at least part of its analgesic action is mediated by active metabolites . In vitro morphine glucuronides enhanced morphine in displacing radiolig and s from the opioid receptors , thus suggesting their complex interactions in vivo CONTEXT There is wide interindividual variation in response to morphine for cancer-related pain ; 30 % of patients do not have a good therapeutic outcome . Alternative opioids such as oxycodone are increasingly being used , and opioid switching has become common clinical practice . OBJECTIVES To compare clinical response to oral morphine vs. oral oxycodone when used as first-line or second-line ( after switching ) treatment in patients with cancer-related pain . METHODS In this prospect i ve , open-label , r and omized , controlled trial ( IS RCT N65155201 ) with a selected crossover phase , patients with cancer-related pain were r and omized to receive either oral morphine or oxycodone as first-line treatment . Dose was individually titrated until the patient reported adequate pain control . Patients who did not respond to the first-line opioid ( either because of inadequate analgesia or unacceptable adverse effects ) were switched to the alternative opioid . RESULTS Two hundred patients were recruited . On intention-to-treat analysis ( n = 198 , morphine 98 , oxycodone 100 ) , there was no significant difference between the numbers of patients responding to morphine ( 61/98 = 62 % ) or oxycodone ( 67/100 = 67 % ) when used as a first-line opioid . Similarly , there was no significant difference in subsequent response when patients were switched to either morphine ( 8/12 = 67 % ) or oxycodone ( 11/21 = 52 % ) . Per- protocol analysis demonstrated a 95 % response rate when both opioids were available . There was no difference in adverse reaction scores between morphine and oxycodone either in first-line responders or nonresponders . CONCLUSION In this population , there was no difference between analgesic response or adverse reactions to oral morphine and oxycodone when used as a first- or second-line opioid . These data provide evidence to support opioid switching to improve outcomes CONTEXT Oxycodone and morphine are recommended as first-choice opioids for moderate/severe cancer pain , but evidence about their relative tolerability has significant method ological limitations . OBJECTIVES This study was mainly aim ed at comparing the risk of developing adverse events ( AEs ) with controlled-release oral morphine vs. oxycodone ; secondary aims were comparing their analgesic efficacy and testing heterogeneity in tolerability across different age and renal function subgroups . METHODS An open-label multicenter RCT ( EudraCT number : 2006 - 003151 - 21 ) was carried out in patients with moderate/severe cancer pain . At baseline , 7 and 14 days , patients scored on 0 - 10 rating scales ( 0 - 10 numerical rating scale ) the intensity of pain and of a list of common opioid side effects . The primary end point was the percentage of patients reporting an AE ( a worsening ≥ 2 points on any of the listed side effects ) ; tolerability by subgroups and average follow-up pain intensity were compared through regression models . RESULTS One hundred eighty-seven patients were enrolled ( 47 % of originally planned ) . Intention to treat ( ITT ) analysis ( N = 185 , morphine 94 , oxycodone 91 ) did not show any difference in the risk of developing AEs ( risk difference -0.6 % , 95 % CI -11.0 % to 9.9 % ) nor in analgesia ( 0 - 10 numerical rating scale pain intensity difference -0.28 , 95 % CI -0.83 to 0.27 ) . No evidence of heterogeneity of tolerability across age and renal function patient subgroups emerged . CONCLUSION This trial failed to show any difference in tolerability and analgesic efficacy  of morphine and oxycodone as first-line treatment for moderate/severe cancer pain but results interpretation is difficult due to lack of power , potential bias from open-label design , and concerns about assay sensitivity . These data , however , can significantly contribute to future meta-analyses comparing WHO Step-III opioids and are relevant in design ing future r and omized studies The antinociceptive effect of morphine and oxycodone is mediated preferentially at μ and κ receptors , respectively . The aim of this study was to evaluate the analgesic profile of the combination of morphine and oxycodone in cancer pain , compared to the st and ard administration of morphine alone . Controlled-release formulations of oxycodone ( CRO ) and morphine ( CRM ) were compared in 26 patients . The study started with an open-label , r and omised titration phase to achieve stable pain control for 7 days , followed by a double-blind , r and omised crossover phase in two periods , 14 days each . At any point , patients were allowed to use oral immediate-release morphine ( IRM ) as needed , in order to keep visual analogue scale ⩽4 . Pain , satisfaction , adverse effects and number of daily rescue morphine tablets were assessed . A total of 22 patients were evaluated .  The weekly upload consumption ratio in morphine/oxycodone was 1 : 1.8 ( 1.80 , 1.83 , 1.76 , 1.84 ) . The weekly IRM consumption was higher in patients having CRM compared to patients having CRO ( ratio morphine/oxycodone : 1.6 , 1.6 , 1.6 , 1.7 ) ( P<0.05 ) . Patients receiving oxycodone complained of less nausea and vomiting . The rescue morphine analgesic consumption was 38 % higher in patients receiving only morphine , compared to patients receiving both morphine and oxycodone . The results suggest that the combination of morphine/oxycodone ( opioids with differential preferential sites of action ) can be a useful alternative to morphine alone , result ing in a better analgesia profile and less emesis Oxycodone is an opioid analgesic that closely resembles morphine . Oxymorphone , the active metabolite of oxycodone , is formed in a reaction catalyzed by CYP2D6 , which is under polymorphic genetic control . The role of oxymorphone in the analgesic effect of oxycodone is not yet clear . In this study , controlled-release ( CR ) oxycodone and morphine were examined in cancer pain . CR oxycodone and morphine were administered to 45 adult patients with stable pain for 3 - 6 days after open-label titration in a r and omized , double-blind , cross-over trial . Twenty patients were evaluable . Both opioids provided adequate analgesia . The variation in plasma morphine concentrations was higher than that of oxycodone , consistent with the lower bioavailability of morphine . Liver dysfunction affected selectively either oxycodone or morphine metabolism . Three patients with markedly aberrant plasma opioid concentrations are presented . Significant individual variation in morphine and oxycodone metabolism may account for abnormal responses during treatment of chronic cancer pain UNLABELLED Noninferiority of the efficacy of once-daily hydromorphone hydrochloride extended-release ( hydromorphone ER ) compared with twice-daily oxycodone hydrochloride controlled-release ( oxycodone CR ) was investigated in this r and omized , double-blind study in Chinese patients with moderate to severe cancer pain requiring strong oral opioid analgesics . R and omization ( 1:1 ) to hydromorphone ER ( 8 - 32 mg ) or oxycodone CR ( 10 - 40 mg ) was followed by dose titration ( up to 8 days ) and dose maintenance ( 28 days , weekly visits ) . Primary endpoint was change from baseline to end of study in " worst pain in the past 24 hours " of Brief Pain Inventory ( Short Form ) score on last observation carried forward ( per protocol set ) . A total of 137 of 260 r and omized patients completed maintenance phase  ( hydromorphone ER : n = 70 ; oxycodone CR : n = 67 ) ; per protocol set : 81 patients . Mean age was 53.1 years ( range : 18 - 70 years ; males : 65.3 % ) ; most common Eastern Cooperative Oncology Group performance status = 2 . Least square mean difference between 2 treatment groups for primary endpoint using analysis of covariance ( baseline score , covariate ) was -.1 ( 95 % confidence interval : -1.3 , 1.1 ) , with upper bound of 95 % confidence interval < 1.5 ( predefined noninferiority margin ) . Most common reason for deaths was disease progression  ( hydromorphone ER : 6.3 % ; oxycodone CR : 12.7 % ) . Treatment-emergent adverse events were comparable between treatment groups . Hydromorphone ER was noninferior to oxycodone  CR in alleviating cancer pain and was well tolerated . PERSPECTIVE This article demonstrates clinical noninferiority of the efficacy of once-daily hydromorphone ER compared with twice-daily oxycodone CR in alleviating cancer pain in Chinese patients , with comparable safety profiles between the 2 treatment groups . Thus , a treatment option with the potential for a reduced dosing frequency exists for health care providers and patients BACKGROUND The European Pain in Cancer survey sought to increase underst and ing of cancer-related pain and treatment across Europe . PATIENTS AND METHODS Patients with all stages of cancer participated in a two-phase telephone survey conducted in 11 European countries and Israel in 2006 - 2007 . The survey screened for patients experiencing pain at least weekly , then r and omly selected adult patients with pain of at least moderate intensity occurring several times per week for the last month completed a detailed attitudinal question naire . RESULTS Of 5084 adult patients contacted , 56 % suffered moderate-to-severe pain at least monthly . Of 573 patients r and omly selected for the second survey phase , 77 % were receiving prescription-only analgesics  , with 41 % taking  strong opioids either alone or with other drugs for cancer-related pain . Of those prescribed analgesics , 63 % experienced breakthrough pain . In all , 69 % reported pain-related difficulties with everyday activities ; however , 50 % believed that their quality of life was not considered a priority in their overall care by their health care professional . CONCLUSIONS Across Europe and Israel , treatment of cancer pain is suboptimal . Pain and pain relief should be considered integral to the diagnosis and treatment of cancer ; management guidelines should be revised to improve pain control in patients with cancer The single-dose pharmacokinetics and pharmacodynamics of oxycodone administered by the intravenous and rectal routes were determined in 12 adult cancer patients with moderate to severe cancer pain ( visual analog scale [ 
    Output:
    
Meta-analyses showed no significant differences between controlled-release ( CR ) and immediate-release oxycodone in pain intensity or adverse events but did show significantly better pain relief after treatment with CR morphine compared with CR oxycodone .
Meta-analyses of the adverse events showed a significantly lower risk of hallucinations after treatment with CR oxycodone compared with CR morphine , but no other differences .
None found any clear superiority or inferiority of oxycodone in pain relief or adverse events .
Conclusions Oxycodone offers similar levels of pain relief and adverse events to other strong opioids .
Our conclusions are consistent with other review s and suggest that oxycodone can be used first line as an alternative to morphine .
However , because it is cheaper , morphine generally remains the first-line opioid of choice