ED; impotency; still get erect, not as hard; doesn't stay up long enough for 2 minutes; still can ejaculate but it doesn't work right; Kidney stone; Low testosterone; on the lower end. Lower 300s; testosterone levels are in the lower 200s 300s; Hypoesthesia; Lack of sensation; I want to be aroused and feel but my penis doesn't work; Can still ejaculate but it doesn't work right; Not pleasing my wife; Did not get second dose; This serious, initial spontaneous safety report was received by Novavax on 11-OCT-2023 from a consumer via the contact center.  A 40-year-old male was vaccinated with intramuscular Novavax Covid-19 Vaccine, Adjuvanted 10 ug/mL suspect Covid-19 vaccine dose 1 on 17-AUG-2022.  Medical history included Hypersensitivity. The individual was reportedly very healthy and active.  Concomitant medications included Claritin (loratadine).  On 17-AUG-2022, the individual received 1 dose of Novavax and did not receive a second dose (PT: Incomplete course of vaccination), which was scheduled for 12-OCT-2022. Ever since the individual had the vaccination, he quickly developed ED (erectile dysfunction) and impotency (PT: Erectile dysfunction) (Serious: Medically Significant). He still felt young, and his penis could get erect, but not as hard. If his penis was erect, it did not stay up long enough for 2 minutes. Since an unspecified date, after vaccination, individual experienced hypoaesthesia and a lack of sensation (PT: Genital hypoaesthesia). It got to a point where the individual wants to be aroused and feel, but his penis didn't work (PT: Disturbance in sexual arousal). He could still ejaculate, but his penis didn't work right. The individual was not pleasing his wife (PT: Sexual dysfunction). The individual did not start any treatment or pills. On 02-JUN-2023, the individual had blood work done, and his testosterone was on the low side, in the lower 200s/300s (units not reported) (PT: Blood testosterone decreased). On 04-AUG-2023, after vaccination, he went to the emergency room with a kidney stone (PT: Nephrolithiasis) (Serious: Medically Significant). On 01-SEP-2023, the individual had more blood work done, and his testosterone levels went up 8 points from 02-JUN-2023.  Relevant lab tests included: SARS-CoV-2 test (Result: Negative; unspecified date), Blood testosterone (Result: Lower 200s/300s (units not reported); 02-JUN-2023), Blood testosterone (Result: Lower 200s/300s (Units not reported); Up 8 points from 02-JUN-2023; 01-SEP-2023), Pancreatic enzymes (Result: Great/low at 2.1 (Units not reported); 02-JUN-2023), Pancreatic enzymes (Result: Great/low at 2.1 (Units not reported); 01-SEP-2023), and Blood test (Result: Amazing; 02-JUN-2023 and 01-SEP-2023).  On 17-AUG-2022, the event outcome of Incomplete course of vaccination was recovered/resolved. At the time of reporting, the event outcomes of Erectile dysfunction, Genital hypoaesthesia, Disturbance in sexual arousal, Sexual dysfunction, and Blood testosterone decreased were not recovered/not resolved. The event outcome of Nephrolithiasis was unknown.; Sender's Comments: This 40-year-old male experienced: Erectile dysfunction, Nephrolithiasis, Incomplete course of vaccination, Blood testosterone decreased, Disturbance in sexual arousal, Genital hypoaesthesia and Sexual dysfunction after vaccination with Novavax Covid-19 Vaccine, Adjuvanted 10 ug/mL. The events Erectile dysfunction and Nephrolithiasis were assessed as serious. The events Incomplete course of vaccination, Blood testosterone decreased, Disturbance in sexual arousal, Genital hypoaesthesia and Sexual dysfunction were reported as non-serious. Based on the spontaneous nature of the report, the causal relationship between Novavax Covid-19 Vaccine, Adjuvanted and the reported events is considered Possible.