
When a single 100 mg dose of sildenafil was administered with erythromycin, a moderate CYP3A4 inhibitor, at steady state (500 mg bid for 5 days), there was a 160% increase in sildenafil Cmax and an 182% increase in sildenafil AUC. In addition, in a study performed in healthy male volunteers, co-administration of the HIV protease inhibitor saquinavir, also a CYP3A4 inhibitor, at steady state (1200 mg tid) with sildenafil (100 mg single dose) resulted in a 140% increase in sildenafil Cmax and a 210% increase in sildenafil AUC. A stronger CYP3A4 inhibitor such as ketoconazole or itraconazole could be expected to have greater effect than that seen with saquinavir.
Results with all doses have been pooled, but scores showed greater improvement at the 50 and 100 mg doses than at the 25 mg dose. The pattern of responses was similar for the other principal question, the ability to achieve an erection sufficient for intercourse. The titration studies, in which most patients received 100 mg, showed similar results. Figure 7 shows that regardless of the baseline levels of function, subsequent function in patients treated with sildenafil was better than that seen in patients treated with placebo. At the same time, on-treatment function was better in treated patients who were less impaired at baseline.
Figure7: Effect of Sildenafil and Placebo on Maintenance of Erection by Baseline Score The frequency of patients reporting improvement of erections in response to a global question in four of the sildenafil randomized, double-blind, parallel, placebo-controlled fixed dose studies (1797 patients) of 12 to 24 weeks duration is shown in Figure 8. These patients had erectile dysfunction at baseline that was characterized by median categorical scores of 2 (a few times) on principal IIEF questions. Erectile dysfunction was attributed to organic (58%; generally not characterized, but including diabetes and excluding spinal cord injury), psychogenic (17%), or mixed (24%) etiologies. Sixty-three percent, 74%, and 82% of the patients on 25 mg, 50 mg and 100 mg of sildenafil, respectively, reported an improvement in their erections, compared to 24% on placebo. Population pharmacokinetic data from patients in clinical trials also indicated a reduction in sildenafil clearance when it was co-administered with CYP3A4 inhibitors (such as ketoconazole, erythromycin, or cimetidine) [ see Dosage and Administration((2.2) and Drug Interactions (7.4)].
| Product | Dosage | Quantity + Bonus | Price | |
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| Kamagra Polo | 100mg | 12 Pills | 60.21€ 57.34€ | |
| Viagra Generic | 50mg | 60 + 4 Pills | 83.93€ 79.93€ | |
| Kamagra Oral Jelly | 100mg | 220 + 18 Sachets | 662.24€ 630.70€ | |
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| Kamagra | 100mg | 120 + 6 Pills | 330.74€ 314.99€ | |
| Kamagra Oral Jelly | 100mg | 110 + 9 Sachets | 334.87€ 318.92€ | |
| Viagra Generic | 50mg | 180 + 8 Pills | 158.82€ 151.26€ | |
| Kamagra Polo | 100mg | 60 + 4 Pills | 189.39€ 180.37€ | |
| Viagra Generic | 150mg | 90 + 6 Pills | 147.18€ 140.17€ | |
| Kamagra Soft Tabs | 100mg | 20 Pills | 79.79€ 75.99€ |
In another study in healthy male volunteers, co-administration with the HIV protease inhibitor ritonavir, which is a highly potent P450 inhibitor, at steady state (500 mg bid) with sildenafil (100 mg single dose) resulted in a 300% (4-fold) increase in sildenafil Cmax and a 1000% (11-fold) increase in sildenafil plasma AUC. At 24 hours the plasma levels of sildenafil were still approximately 200 ng/mL, compared to approximately 5 ng/mL when sildenafil was dosed alone. This is consistent with ritonavir’s marked effects on a broad range of P450 substrates. Sildenafil had no effect on ritonavir pharmacokinetics [ see Dosage and Administration (2.2) and Drug Interactions (7.4)]. Although the interaction between other protease inhibitors and sildenafil has not been studied, their concomitant use is expected to increase sildenafil levels. In a study of healthy male volunteers, co-administration of sildenafil at steady state (80 mg t.i.d.) with endothelin receptor antagonist bosentan (a moderate inducer of CYP3A4, CYP2C9 and possibly of CYP2C19) at steady state (125 mg b.i.d.) resulted in a 63% decrease of sildenafil AUC and a 55% decrease in sildenafil Cmax.
A total of 475 patients were enrolled and received treatment with SILDENAFIL ORAL FILM, including subjects with comorbidities such as diabetes, dyslipidemia, hypertension and obesity. Of these, 354 patients received SILDENAFIL ORAL FILM and 121 patients received placebo without regard to food and alcohol concomitant intake. The initial dose was 50 mg for subjects under 65 years and 25 mg for subjects 65 years or older with dose adjustment permitted up to 50 mg (for subjects 65 years or older), 75 mg or 100 mg or down to 25 mg based on efficacy and tolerability. By the end of the study, 94 (26.6%) and 115 (32.5%) patients in the SILDENAFIL ORAL FILM group were receiving 75 mg or 100 mg respectively. The efficacy of SILDENAFIL ORAL FILM, administered at flexible doses of 25 mg, 50 mg, 75 mg and 100 mg for the treatment of ED, was superior to placebo.
Efficacy results are shown in Figure 6. Subgroup analyses by age, race, and ethnicity showed efficacy results consistent with the overall population. *Statistically significant differences vs. placebo; p-value <0.001 IIEF= International Index of Erectile Function, EF = Erectile Function, SEP Q2=Sexual Encounter Profile Question 2, SEP Q3 = Sexual Encounter Profile Question 3, N = Number of Subjects, SD = Standard Deviation, LS = Least Squares, CI = Confidence Interval. Sildenafil was assessed in many clinical studies for its effect on the ability of men with ED to engage in sexual activity and in many cases specifically on the ability to achieve and maintain an erection sufficient for satisfactory sexual activity.
Sildenafil was evaluated primarily at doses of 25 mg, 50 mg and 100 mg in 21 randomized, double-blind, placebo-controlled trials of up to 6 months in duration, using a variety of study designs (fixed dose, titration, parallel, crossover). Sildenafil was administered to more than 3,000 patients aged 19 to 87 years, with ED of various etiologies (organic, psychogenic, mixed) with a mean duration of 5 years. sildenafil citrate demonstrated statistically significant improvement compared to placebo in all 21 studies. The studies that established benefit demonstrated improvements in success rates for sexual intercourse compared with placebo. Sildenafil Efficacy Results from Controlled Clinical Studies The effect of sildenafil on one of the major end points, maintenance of erections after penetration, is shown in Figure 7, for the pooled results of 5 sildenafil fixed-dose, dose-response studies of greater than one-month duration, showing response according to baseline function. Concomitant administration of strong CYP3A4 inducers, such as rifampin, is expected to cause greater decreases in plasma levels of sildenafil.
| Side Effect | Frequency | Severity | Management | Notes |
|---|---|---|---|---|
| Headache | Common | Mild | Analgesics, hydration | Usually transient |
| Flushing | Common | Mild | Cooling measures | May subside quickly |
| Nasal Congestion | Less common | Mild | Decongestants if needed | Temporary sensation |
| Dizziness | Occasional | Variable | Stable position, hydration | Caution in motor activities |
| Visual disturbances | Rare | Moderate | Seek medical advice | Usually reversible |
Single doses of antacid (magnesium hydroxide/aluminum hydroxide) did not affect the bioavailability of sildenafil citrate.
These effects on the metabolite are not expected to be of clinical consequence. Given sildenafil peak plasma concentrations of approximately 1 μM after recommended doses, it is unlikely that sildenafil will alter the clearance of substrates of these isoenzymes. No significant interactions were shown with tolbutamide (250 mg) or warfarin (40 mg), both of which are metabolized by CYP2C9. In a study of healthy male volunteers, sildenafil (100 mg) did not affect the steady state pharmacokinetics of the HIV protease inhibitors, saquinavir and ritonavir, both of which are CYP3A4 substrates. Sildenafil (50 mg) did not potentiate the increase in bleeding time caused by aspirin (150 mg).
Sildenafil at steady state, at a dose not approved for the treatment of erectile dysfunction (80 mg t.i.d.) resulted in a 50% increase in AUC and a 42% increase in Cmax of bosentan (125 mg b.i.d.). Sildenafil was not carcinogenic when administered to rats for 24 months at a dose resulting in total systemic drug exposure (AUCs) for unbound sildenafil and its major metabolite of 20- and 38- times, for male and female rats, respectively, the exposures observed in human males given the Maximum Recommended Human Dose (MRHD) of 100 mg. Sildenafil was not carcinogenic when administered to mice for 18-21 months at dosages up to the Maximum Tolerated Dose (MTD) of 10 mg/kg/day, approximately 0.4 times the MRHD on a mg/m 2basis in a 50 kg subject. There was no impairment of fertility in rats given sildenafil up to 60 mg/kg/day for 36 days to females and 102 days to males, a dose producing an AUC value of more than 25 times the human male AUC. The efficacy of SILDENAFIL ORAL FILM in the treatment of erectile dysfunction was established in part on the basis of efficacy data from trials with the tablet formulation of sildenafil.
SILDENAFIL ORAL FILM was evaluated in one randomized, double-blind, placebo-controlled, flexible-dose study (25 mg, 50 mg, 75 mg, 100 mg) over 12 weeks study to evaluate the erectile function of men with erectile dysfunction (ED). The co-primary efficacy endpoints included both a 4-week assessment of sexual function based on the International Index of Erectile Function (IIEF) questionnaire and an assessment of sexual function after each sexual intercourse based on the Sexual Encounter Profile (SEP) on the daily diary. The six-item, 30-point, erectile function (EF) domain of the IIEF was assessed at baseline, at follow-up visits, and at the end of the study reflecting subjects’ sexual experience during the past 4 weeks. The SEP Question 2 (“Were you able to insert your penis into your partner’s vagina”) and Question 3 (“Did your erection last long enough for you to have successful intercourse?”) were answered immediately after each sexual attempt with binary response (Yes=success, No=failure). Sexual function data were recorded by patients sildenafil oral jelly 100mg in a daily diary. In healthy male volunteers, there was no evidence of a clinically significant effect of azithromycin (500 mg daily for 3 days) on the systemic exposure of sildenafil or its major circulating metabolite. Pharmacokinetic data from patients in clinical trials showed no effect on sildenafil pharmacokinetics of CYP2C9 inhibitors (such as tolbutamide, warfarin), CYP2D6 inhibitors (such as selective serotonin reuptake inhibitors, tricyclic antidepressants), thiazide and related diuretics, ACE inhibitors, and calcium channel blockers. The AUC of the active metabolite, N-desmethyl sildenafil, was increased 62% by loop and potassium-sparing diuretics and 102% by nonspecific beta-blockers. These effects on the metabolite are not expected to be of clinical consequence. Given sildenafil peak plasma concentrations of approximately 1 μM after recommended doses, it is unlikely that sildenafil will alter the clearance of substrates of these isoenzymes. No significant interactions were shown with tolbutamide (250 mg) or warfarin (40 mg), both of which are metabolized by CYP2C9. In a study of healthy male volunteers, sildenafil (100 mg) did not affect the steady state pharmacokinetics of the HIV protease inhibitors, saquinavir and ritonavir, both of which are CYP3A4 substrates. Sildenafil (50 mg) did not potentiate the increase in bleeding time caused by aspirin (150 mg). Sildenafil at steady state, at a dose not approved for the treatment of erectile dysfunction (80 mg t.i.d.) resulted in a 50% increase in AUC and a 42% increase in Cmax of bosentan (125 mg b.i.d.). Sildenafil was not carcinogenic when administered to rats for 24 months at a dose resulting in total systemic drug exposure (AUCs) for unbound sildenafil and its major metabolite of 20- and 38- times, for male and female rats, respectively, the exposures observed in human males given the Maximum Recommended Human Dose (MRHD) of 100 mg. Sildenafil was not carcinogenic when administered to mice for 18-21 months at dosages up to the Maximum Tolerated Dose (MTD) of 10 mg/kg/day, approximately 0.4 times the MRHD on a mg/m 2basis in a 50 kg subject. There was no impairment of fertility in rats given sildenafil up to 60 mg/kg/day for 36 days to females and 102 days to males, a dose producing an AUC value of more than 25 times the human male AUC. The efficacy of SILDENAFIL ORAL FILM in the treatment of erectile dysfunction was established in part on the basis of efficacy data from trials with the tablet formulation of sildenafil.
SILDENAFIL ORAL FILM was evaluated in one randomized, double-blind, placebo-controlled, flexible-dose study (25 mg, 50 mg, 75 mg, 100 mg) over 12 weeks study to evaluate the erectile function of men with erectile dysfunction (ED). The co-primary efficacy endpoints included both a 4-week assessment of sexual function based on the International Index of Erectile Function (IIEF) questionnaire and an assessment of sexual function after each sexual intercourse based on the Sexual Encounter Profile (SEP) on the daily diary. The six-item, 30-point, erectile function (EF) domain of the IIEF was assessed at baseline, at follow-up visits, and at the end of the study reflecting subjects’ sexual experience during the past 4 weeks. The SEP Question 2 (“Were you able to insert your penis into your partner’s vagina”) and Question 3 (“Did your erection last long enough for you to have successful intercourse?”) were answered immediately after each sexual attempt with binary response (Yes=success, No=failure). Sexual function data were recorded by patients sildenafil oral jelly 100mg in a daily diary. A total of 475 patients were enrolled and received treatment with SILDENAFIL ORAL FILM, including subjects with comorbidities such as diabetes, dyslipidemia, hypertension and obesity. Of these, 354 patients received SILDENAFIL ORAL FILM and 121 patients received placebo without regard to food and alcohol concomitant intake. The initial dose was 50 mg for subjects under 65 years and 25 mg for subjects 65 years or older with dose adjustment permitted up to 50 mg (for subjects 65 years or older), 75 mg or 100 mg or down to 25 mg based on efficacy and tolerability.
By the end of the study, 94 (26.6%) and 115 (32.5%) patients in the SILDENAFIL ORAL FILM group were receiving 75 mg or 100 mg respectively.
When a single 100 mg dose of sildenafil was administered with erythromycin, a moderate CYP3A4 inhibitor, at steady state (500 mg bid for 5 days), there was a 160% increase in sildenafil Cmax and an 182% increase in sildenafil AUC. In addition, in a study performed in healthy male volunteers, co-administration of the HIV protease inhibitor saquinavir, also a CYP3A4 inhibitor, at steady state (1200 mg tid) with sildenafil (100 mg single dose) resulted in a 140% increase in sildenafil Cmax and a 210% increase in sildenafil AUC. A stronger CYP3A4 inhibitor such as ketoconazole or itraconazole could be expected to have greater effect than that seen with saquinavir. Population pharmacokinetic data from patients in clinical trials also indicated a reduction in sildenafil clearance when it was co-administered with CYP3A4 inhibitors (such as ketoconazole, erythromycin, or cimetidine) [ see Dosage and Administration((2.2) and Drug Interactions (7.4)]. In another study in healthy male volunteers, co-administration with the HIV protease inhibitor ritonavir, which is a highly potent P450 inhibitor, at steady state (500 mg bid) with sildenafil (100 mg single dose) resulted in a 300% (4-fold) increase in sildenafil Cmax and a 1000% (11-fold) increase in sildenafil plasma AUC.
At 24 hours the plasma levels of sildenafil were still approximately 200 ng/mL, compared to approximately 5 ng/mL when sildenafil was dosed alone. This is consistent with ritonavir’s marked effects on a broad range of P450 substrates. Sildenafil had no effect on ritonavir pharmacokinetics [ see Dosage and Administration (2.2) and Drug Interactions (7.4)]. Although the interaction between other protease inhibitors and sildenafil has not been studied, their concomitant use is expected to increase sildenafil levels. In a study of healthy male volunteers, co-administration of sildenafil at steady state (80 mg t.i.d.) with endothelin receptor antagonist bosentan (a moderate inducer of CYP3A4, CYP2C9 and possibly of CYP2C19) at steady state (125 mg b.i.d.) resulted in a 63% decrease of sildenafil AUC and a 55% decrease in sildenafil Cmax.
Concomitant administration of strong CYP3A4 inducers, such as rifampin, is expected to cause greater decreases in plasma levels of sildenafil. Single doses of antacid (magnesium hydroxide/aluminum hydroxide) did not affect the bioavailability of sildenafil citrate. In healthy male volunteers, there was no evidence of a clinically significant effect of azithromycin (500 mg daily for 3 days) on the systemic exposure of sildenafil or its major circulating metabolite. Pharmacokinetic data from patients in clinical trials showed no effect on sildenafil pharmacokinetics of CYP2C9 inhibitors (such as tolbutamide, warfarin), CYP2D6 inhibitors (such as selective serotonin reuptake inhibitors, tricyclic antidepressants), thiazide and related diuretics, ACE inhibitors, and calcium channel blockers. The AUC of the active metabolite, N-desmethyl sildenafil, was increased 62% by loop and potassium-sparing diuretics and 102% by nonspecific beta-blockers. The efficacy of SILDENAFIL ORAL FILM, administered at flexible doses of 25 mg, 50 mg, 75 mg and 100 mg for the treatment of ED, was superior to placebo. Efficacy results are shown in Figure 6.
Subgroup analyses by age, race, and ethnicity showed efficacy results consistent with the overall population. *Statistically significant differences vs. placebo; p-value <0.001 IIEF= International Index of Erectile Function, EF = Erectile Function, SEP Q2=Sexual Encounter Profile Question 2, SEP Q3 = Sexual Encounter Profile Question 3, N = Number of Subjects, SD = Standard Deviation, LS = Least Squares, CI = Confidence Interval.
Sildenafil was assessed in many clinical studies for its effect on the ability of men with ED to engage in sexual activity and in many cases specifically on the ability to achieve and maintain an erection sufficient for satisfactory sexual activity. Sildenafil was evaluated primarily at doses of 25 mg, 50 mg and 100 mg in 21 randomized, double-blind, placebo-controlled trials of up to 6 months in duration, using a variety of study designs (fixed dose, titration, parallel, crossover). Sildenafil was administered to more than 3,000 patients aged 19 to 87 years, with ED of various etiologies (organic, psychogenic, mixed) with a mean duration of 5 years. sildenafil citrate demonstrated statistically significant improvement compared to placebo in all 21 studies. The studies that established benefit demonstrated improvements in success rates for sexual intercourse compared with placebo. Sildenafil Efficacy Results from Controlled Clinical Studies The effect of sildenafil on one of the major end points, maintenance of erections after penetration, is shown in Figure 7, for the pooled results of 5 sildenafil fixed-dose, dose-response studies of greater than one-month duration, showing response according to baseline function. Results with all doses have been pooled, but scores showed greater improvement at the 50 and 100 mg doses than at the 25 mg dose. The pattern of responses was similar for the other principal question, the ability to achieve an erection sufficient for intercourse. The titration studies, in which most patients received 100 mg, showed similar results. Figure 7 shows that regardless of the baseline levels of function, subsequent function in patients treated with sildenafil was better than that seen in patients treated with placebo. At the same time, on-treatment function was better in treated patients who were less impaired at baseline. Figure7: Effect of Sildenafil and Placebo on Maintenance of Erection by Baseline Score The frequency of patients reporting improvement of erections in response to a global question in four of the sildenafil randomized, double-blind, parallel, placebo-controlled fixed dose studies (1797 patients) of 12 to 24 weeks duration is shown in Figure 8. These patients had erectile dysfunction at baseline that was characterized by median categorical scores of 2 (a few times) on principal IIEF questions. Erectile dysfunction was attributed to organic (58%; generally not characterized, but including diabetes and excluding spinal cord injury), psychogenic (17%), or mixed (24%) etiologies.
| Brand Name | Manufacturer | Price Range | Availability | FDA Approval Status |
|---|---|---|---|---|
| Strips of Eros | PharmaX Ltd. | $15 - $25 | Online, pharmacies | Approved |
| VistoStrips | MedSolutions Inc. | $20 - $30 | Distributors | Pending approval |
| OralEase | BioHealth Corp. | $17 - $24 | Specialty stores | Approved |
| QuickDissolve | NutraPharma | $18 - $28 | Online marketplaces | Approved |
| FastRelief | HealthGen | $16 - $22 | Pharmacies, online | Approved |
Sixty-three percent, 74%, and 82% of the patients on 25 mg, 50 mg and 100 mg of sildenafil, respectively, reported an improvement in their erections, compared to 24% on placebo.